diff --git a/init.php b/init.php
index b60d2181f..99f7a8c1b 100644
--- a/init.php
+++ b/init.php
@@ -50,7 +50,6 @@
 require(dirname(__FILE__) . '/lib/ApiRequestor.php');
 require(dirname(__FILE__) . '/lib/ApiResource.php');
 require(dirname(__FILE__) . '/lib/SingletonApiResource.php');
-require(dirname(__FILE__) . '/lib/ExternalAccount.php');
 
 // Stripe API Resources
 require(dirname(__FILE__) . '/lib/Account.php');
diff --git a/lib/Account.php b/lib/Account.php
index e50207a66..e4a5cc4e2 100644
--- a/lib/Account.php
+++ b/lib/Account.php
@@ -120,7 +120,7 @@ public function deauthorize($clientId = null, $opts = null)
      * @param array|null $params
      * @param array|string|null $opts
      *
-     * @return ExternalAccount
+     * @return BankAccount|Card
      */
     public static function createExternalAccount($id, $params = null, $opts = null)
     {
@@ -133,7 +133,7 @@ public static function createExternalAccount($id, $params = null, $opts = null)
      * @param array|null $params
      * @param array|string|null $opts
      *
-     * @return ExternalAccount
+     * @return BankAccount|Card
      */
     public static function retrieveExternalAccount($id, $externalAccountId, $params = null, $opts = null)
     {
@@ -146,7 +146,7 @@ public static function retrieveExternalAccount($id, $externalAccountId, $params
      * @param array|null $params
      * @param array|string|null $opts
      *
-     * @return ExternalAccount
+     * @return BankAccount|Card
      */
     public static function updateExternalAccount($id, $externalAccountId, $params = null, $opts = null)
     {
@@ -159,7 +159,7 @@ public static function updateExternalAccount($id, $externalAccountId, $params =
      * @param array|null $params
      * @param array|string|null $opts
      *
-     * @return ExternalAccount
+     * @return BankAccount|Card
      */
     public static function deleteExternalAccount($id, $externalAccountId, $params = null, $opts = null)
     {
@@ -171,7 +171,7 @@ public static function deleteExternalAccount($id, $externalAccountId, $params =
      * @param array|null $params
      * @param array|string|null $opts
      *
-     * @return ExternalAccount
+     * @return BankAccount|Card
      */
     public static function allExternalAccounts($id, $params = null, $opts = null)
     {
diff --git a/lib/AlipayAccount.php b/lib/AlipayAccount.php
index 1ba34bfa6..fb7d5bb79 100644
--- a/lib/AlipayAccount.php
+++ b/lib/AlipayAccount.php
@@ -6,8 +6,64 @@
  * Class AlipayAccount
  *
  * @package Stripe
+ *
+ * @deprecated Alipay accounts are deprecated. Please use the sources API instead.
+ * @link https://stripe.com/docs/sources/alipay
  */
-class AlipayAccount extends ExternalAccount
+class AlipayAccount extends ApiResource
 {
+    use ApiOperations\Delete;
+    use ApiOperations\Update;
+
+    /**
+     * @return string The instance URL for this resource. It needs to be special
+     *    cased because it doesn't fit into the standard resource pattern.
+     */
+    public function instanceUrl()
+    {
+        if ($this['customer']) {
+            $base = Customer::classUrl();
+            $parent = $this['customer'];
+            $path = 'sources';
+        } else {
+            $msg = "Alipay accounts cannot be accessed without a customer ID.";
+            throw new Error\InvalidRequest($msg, null);
+        }
+        $parentExtn = urlencode(Util\Util::utf8($parent));
+        $extn = urlencode(Util\Util::utf8($this['id']));
+        return "$base/$parentExtn/$path/$extn";
+    }
+
+    /**
+     * @param array|string $_id
+     * @param array|string|null $_opts
+     *
+     * @throws \Stripe\Error\InvalidRequest
+     *
+     * @deprecated Alipay accounts are deprecated. Please use the sources API instead.
+     * @link https://stripe.com/docs/sources/alipay
+     */
+    public static function retrieve($_id, $_opts = null)
+    {
+        $msg = "Alipay accounts cannot be accessed without a customer ID. " .
+               "Retrieve an Alipay account using \$customer->sources->retrieve('alipay_account_id') instead.";
+        throw new Error\InvalidRequest($msg, null);
+    }
 
+    /**
+     * @param string $_id
+     * @param array|null $_params
+     * @param array|string|null $_options
+     *
+     * @throws \Stripe\Error\InvalidRequest
+     *
+     * @deprecated Alipay accounts are deprecated. Please use the sources API instead.
+     * @link https://stripe.com/docs/sources/alipay
+     */
+    public static function update($_id, $_params = null, $_options = null)
+    {
+        $msg = "Alipay accounts cannot be accessed without a customer ID. " .
+               "Call save() on \$customer->sources->retrieve('alipay_account_id') instead.";
+        throw new Error\InvalidRequest($msg, null);
+    }
 }
diff --git a/lib/BankAccount.php b/lib/BankAccount.php
index 2f11c067c..43e4498d0 100644
--- a/lib/BankAccount.php
+++ b/lib/BankAccount.php
@@ -7,9 +7,64 @@
  *
  * @package Stripe
  */
-class BankAccount extends ExternalAccount
+class BankAccount extends ApiResource
 {
+    use ApiOperations\Delete;
+    use ApiOperations\Update;
+
     /**
+     * @return string The instance URL for this resource. It needs to be special
+     *    cased because it doesn't fit into the standard resource pattern.
+     */
+    public function instanceUrl()
+    {
+        if ($this['customer']) {
+            $base = Customer::classUrl();
+            $parent = $this['customer'];
+            $path = 'sources';
+        } elseif ($this['account']) {
+            $base = Account::classUrl();
+            $parent = $this['account'];
+            $path = 'external_accounts';
+        } else {
+            $msg = "Bank accounts cannot be accessed without a customer ID or account ID.";
+            throw new Error\InvalidRequest($msg, null);
+        }
+        $parentExtn = urlencode(Util\Util::utf8($parent));
+        $extn = urlencode(Util\Util::utf8($this['id']));
+        return "$base/$parentExtn/$path/$extn";
+    }
+
+    /**
+     * @param array|string $_id
+     * @param array|string|null $_opts
+     *
+     * @throws \Stripe\Error\InvalidRequest
+     */
+    public static function retrieve($_id, $_opts = null)
+    {
+        $msg = "Bank accounts cannot be accessed without a customer ID or account ID. " .
+               "Retrieve a bank account using \$customer->sources->retrieve('bank_account_id') or " .
+               "\$account->external_accounts->retrieve('bank_account_id') instead.";
+        throw new Error\InvalidRequest($msg, null);
+    }
+
+    /**
+     * @param string $_id
+     * @param array|null $_params
+     * @param array|string|null $_options
+     *
+     * @throws \Stripe\Error\InvalidRequest
+     */
+    public static function update($_id, $_params = null, $_options = null)
+    {
+        $msg = "Bank accounts cannot be accessed without a customer ID or account ID. " .
+               "Call save() on \$customer->sources->retrieve('bank_account_id') or " .
+               "\$account->external_accounts->retrieve('bank_account_id') instead.";
+        throw new Error\InvalidRequest($msg, null);
+    }
+
+   /**
      * @param array|null $params
      * @param array|string|null $options
      *
diff --git a/lib/BitcoinReceiver.php b/lib/BitcoinReceiver.php
index db7dfc5f0..8d04256b5 100644
--- a/lib/BitcoinReceiver.php
+++ b/lib/BitcoinReceiver.php
@@ -4,20 +4,20 @@
 
 /**
  * Class BitcoinReceiver
-
- * @deprecated Please use sources instead.
+ *
+ * @package Stripe
+ *
+ * @deprecated Bitcoin receivers are deprecated. Please use the sources API instead.
+ * @link https://stripe.com/docs/sources/bitcoin
  */
-class BitcoinReceiver extends ExternalAccount
+class BitcoinReceiver extends ApiResource
 {
     use ApiOperations\All;
-    use ApiOperations\Create;
     use ApiOperations\Retrieve;
 
     /**
      * @return string The class URL for this resource. It needs to be special
      *    cased because it doesn't fit into the standard resource pattern.
-     *
-     * @deprecated Please use sources instead.
      */
     public static function classUrl()
     {
@@ -27,36 +27,20 @@ public static function classUrl()
     /**
      * @return string The instance URL for this resource. It needs to be special
      *    cased because it doesn't fit into the standard resource pattern.
-     *
-     * @deprecated Please use sources instead.
      */
     public function instanceUrl()
     {
-        $result = parent::instanceUrl();
-        if ($result) {
-            return $result;
+        if ($this['customer']) {
+            $base = Customer::classUrl();
+            $parent = $this['customer'];
+            $path = 'sources';
+            $parentExtn = urlencode(Util\Util::utf8($parent));
+            $extn = urlencode(Util\Util::utf8($this['id']));
+            return "$base/$parentExtn/$path/$extn";
         } else {
-            $id = $this['id'];
-            $id = Util\Util::utf8($id);
-            $extn = urlencode($id);
             $base = BitcoinReceiver::classUrl();
+            $extn = urlencode(Util\Util::utf8($this['id']));
             return "$base/$extn";
         }
     }
-
-    /**
-     * @param array|null $params
-     * @param array|string|null $options
-     *
-     * @return BitcoinReceiver The refunded Bitcoin Receiver item.
-     *
-     * @deprecated Please use sources instead.
-     */
-    public function refund($params = null, $options = null)
-    {
-        $url = $this->instanceUrl() . '/refund';
-        list($response, $opts) = $this->_request('post', $url, $params, $options);
-        $this->refreshFrom($response, $opts);
-        return $this;
-    }
 }
diff --git a/lib/Card.php b/lib/Card.php
index 01ad27847..0b725512f 100644
--- a/lib/Card.php
+++ b/lib/Card.php
@@ -19,7 +19,7 @@
  * @property string $country
  * @property string $customer
  * @property string $cvc_check
- * @property string $dynamic_last4": null,
+ * @property string $dynamic_last4
  * @property int $exp_month
  * @property int $exp_year
  * @property string $fingerprint
@@ -31,7 +31,67 @@
  *
  * @package Stripe
  */
-class Card extends ExternalAccount
+class Card extends ApiResource
 {
+    use ApiOperations\Delete;
+    use ApiOperations\Update;
 
+    /**
+     * @return string The instance URL for this resource. It needs to be special
+     *    cased because cards are nested resources that may belong to different
+     *    top-level resources.
+     */
+    public function instanceUrl()
+    {
+        if ($this['customer']) {
+            $base = Customer::classUrl();
+            $parent = $this['customer'];
+            $path = 'sources';
+        } elseif ($this['account']) {
+            $base = Account::classUrl();
+            $parent = $this['account'];
+            $path = 'external_accounts';
+        } elseif ($this['recipient']) {
+            $base = Recipient::classUrl();
+            $parent = $this['recipient'];
+            $path = 'cards';
+        } else {
+            $msg = "Cards cannot be accessed without a customer ID, account ID or recipient ID.";
+            throw new Error\InvalidRequest($msg, null);
+        }
+        $parentExtn = urlencode(Util\Util::utf8($parent));
+        $extn = urlencode(Util\Util::utf8($this['id']));
+        return "$base/$parentExtn/$path/$extn";
+    }
+
+    /**
+     * @param array|string $_id
+     * @param array|string|null $_opts
+     *
+     * @throws \Stripe\Error\InvalidRequest
+     */
+    public static function retrieve($_id, $_opts = null)
+    {
+        $msg = "Cards cannot be accessed without a customer, recipient or account ID. " .
+               "Retrieve a card using \$customer->sources->retrieve('card_id'), " .
+               "\$recipient->cards->retrieve('card_id'), or";
+               "\$account->external_accounts->retrieve('card_id') instead.";
+        throw new Error\InvalidRequest($msg, null);
+    }
+
+    /**
+     * @param string $_id
+     * @param array|null $_params
+     * @param array|string|null $_options
+     *
+     * @throws \Stripe\Error\InvalidRequest
+     */
+    public static function update($_id, $_params = null, $_options = null)
+    {
+        $msg = "Cards cannot be accessed without a customer, recipient or account ID. " .
+               "Call save() on \$customer->sources->retrieve('card_id'), " .
+               "\$recipient->cards->retrieve('card_id'), or";
+               "\$account->external_accounts->retrieve('card_id') instead.";
+        throw new Error\InvalidRequest($msg, null);
+    }
 }
diff --git a/lib/Customer.php b/lib/Customer.php
index e837222df..9f39699d6 100644
--- a/lib/Customer.php
+++ b/lib/Customer.php
@@ -139,7 +139,7 @@ public function deleteDiscount()
      * @param array|null $params
      * @param array|string|null $opts
      *
-     * @return ExternalAccount
+     * @return ApiResource
      */
     public static function createSource($id, $params = null, $opts = null)
     {
@@ -152,7 +152,7 @@ public static function createSource($id, $params = null, $opts = null)
      * @param array|null $params
      * @param array|string|null $opts
      *
-     * @return ExternalAccount
+     * @return ApiResource
      */
     public static function retrieveSource($id, $sourceId, $params = null, $opts = null)
     {
@@ -165,7 +165,7 @@ public static function retrieveSource($id, $sourceId, $params = null, $opts = nu
      * @param array|null $params
      * @param array|string|null $opts
      *
-     * @return ExternalAccount
+     * @return ApiResource
      */
     public static function updateSource($id, $sourceId, $params = null, $opts = null)
     {
@@ -178,7 +178,7 @@ public static function updateSource($id, $sourceId, $params = null, $opts = null
      * @param array|null $params
      * @param array|string|null $opts
      *
-     * @return ExternalAccount
+     * @return ApiResource
      */
     public static function deleteSource($id, $sourceId, $params = null, $opts = null)
     {
@@ -190,7 +190,7 @@ public static function deleteSource($id, $sourceId, $params = null, $opts = null
      * @param array|null $params
      * @param array|string|null $opts
      *
-     * @return ExternalAccount
+     * @return ApiResource
      */
     public static function allSources($id, $params = null, $opts = null)
     {
diff --git a/lib/ExternalAccount.php b/lib/ExternalAccount.php
deleted file mode 100644
index dff99f722..000000000
--- a/lib/ExternalAccount.php
+++ /dev/null
@@ -1,83 +0,0 @@
-<?php
-
-namespace Stripe;
-
-/**
- * Class ExternalAccount
- *
- * @property string $id
- * @property string $object
- *
- * @package Stripe
- */
-abstract class ExternalAccount extends ApiResource
-{
-    use ApiOperations\Delete;
-
-    /**
-     * @return string The instance URL for this resource. It needs to be special
-     *    cased because it doesn't fit into the standard resource pattern.
-     */
-    public function instanceUrl()
-    {
-        $id = $this['id'];
-        if (!$id) {
-            $class = get_class($this);
-            $msg = "Could not determine which URL to request: $class instance "
-             . "has invalid ID: $id";
-            throw new Error\InvalidRequest($msg, null);
-        }
-
-        if ($this['customer']) {
-            $parent = $this['customer'];
-            $base = Customer::classUrl();
-            $path = 'sources';
-        } elseif ($this['account']) {
-            $parent = $this['account'];
-            $base = Account::classUrl();
-            $path = 'external_accounts';
-        } elseif ($this['recipient']) {
-            $parent = $this['recipient'];
-            $base = Recipient::classUrl();
-            $path = 'cards';
-        } else {
-            return null;
-        }
-
-        $parent = Util\Util::utf8($parent);
-        $id = Util\Util::utf8($id);
-
-        $parentExtn = urlencode($parent);
-        $extn = urlencode($id);
-        return "$base/$parentExtn/$path/$extn";
-    }
-
-    /**
-     * @param array|string|null $opts
-     *
-     * @return ExternalAccount The saved external account.
-     */
-    public function save($opts = null)
-    {
-        return $this->_save($opts);
-    }
-
-    /**
-     * @param array|null $params
-     * @param array|string|null $opts
-     *
-     * @return ExternalAccount The verified (or not) external account.
-     */
-    public function verify($params = null, $opts = null)
-    {
-        if ($this['customer']) {
-            $url = $this->instanceUrl() . '/verify';
-            list($response, $options) = $this->_request('post', $url, $params, $opts);
-            $this->refreshFrom($response, $options);
-            return $this;
-        } else {
-            $message = 'Only customer external accounts can be verified in this manner.';
-            throw new Error\Api($message);
-        }
-    }
-}
diff --git a/tests/Stripe/AlipayAccountTest.php b/tests/Stripe/AlipayAccountTest.php
new file mode 100644
index 000000000..7159f5444
--- /dev/null
+++ b/tests/Stripe/AlipayAccountTest.php
@@ -0,0 +1,76 @@
+<?php
+
+namespace Stripe;
+
+class AlipayAccountTest extends TestCase
+{
+    const TEST_RESOURCE_ID = 'aliacc_123';
+
+    // Because of the wildcard nature of sources, stripe-mock cannot currently
+    // reliably return sources of a given type, so we create a fixture manually
+    public function createFixture($params = [])
+    {
+        if (empty($params)) {
+            $params['customer'] = 'cus_123';
+        }
+        $base = [
+            'id' => self::TEST_RESOURCE_ID,
+            'object' => 'card',
+            'metadata' => [],
+        ];
+        return AlipayAccount::constructFrom(
+            array_merge($params, $base),
+            new Util\RequestOptions()
+        );
+    }
+
+    public function testHasCorrectUrlForCustomer()
+    {
+        $resource = $this->createFixture(['customer' => 'cus_123']);
+        $this->assertSame(
+            "/v1/customers/cus_123/sources/" . self::TEST_RESOURCE_ID,
+            $resource->instanceUrl()
+        );
+    }
+
+    /**
+     * @expectedException \Stripe\Error\InvalidRequest
+     */
+    public function testIsNotDirectlyRetrievable()
+    {
+        AlipayAccount::retrieve(self::TEST_RESOURCE_ID);
+    }
+
+    public function testIsSaveable()
+    {
+        $resource = $this->createFixture();
+        $resource->metadata["key"] = "value";
+        $this->expectsRequest(
+            'post',
+            '/v1/customers/cus_123/sources/' . self::TEST_RESOURCE_ID
+        );
+        $resource->save();
+        $this->assertSame("Stripe\\AlipayAccount", get_class($resource));
+    }
+
+    /**
+     * @expectedException \Stripe\Error\InvalidRequest
+     */
+    public function testIsNotDirectlyUpdatable()
+    {
+        AlipayAccount::update(self::TEST_RESOURCE_ID, [
+            "metadata" => ["key" => "value"],
+        ]);
+    }
+
+    public function testIsDeletable()
+    {
+        $resource = $this->createFixture();
+        $this->expectsRequest(
+            'delete',
+            '/v1/customers/cus_123/sources/' . self::TEST_RESOURCE_ID
+        );
+        $resource->delete();
+        $this->assertSame("Stripe\\AlipayAccount", get_class($resource));
+    }
+}
diff --git a/tests/Stripe/BankAccountTest.php b/tests/Stripe/BankAccountTest.php
index 3597c2bbf..ab1dff9d5 100644
--- a/tests/Stripe/BankAccountTest.php
+++ b/tests/Stripe/BankAccountTest.php
@@ -6,13 +6,86 @@ class BankAccountTest extends TestCase
 {
     const TEST_RESOURCE_ID = 'ba_123';
 
-    public function testIsVerifiable()
+    // Because of the wildcard nature of sources, stripe-mock cannot currently
+    // reliably return sources of a given type, so we create a fixture manually
+    public function createFixture($params = [])
     {
-        $resource = BankAccount::constructFrom([
+        if (empty($params)) {
+            $params['customer'] = 'cus_123';
+        }
+        $base = [
             'id' => self::TEST_RESOURCE_ID,
             'object' => 'bank_account',
-            'customer' => 'cus_123',
+            'metadata' => [],
+        ];
+        return BankAccount::constructFrom(
+            array_merge($params, $base),
+            new Util\RequestOptions()
+        );
+    }
+
+    public function testHasCorrectUrlForCustomer()
+    {
+        $resource = $this->createFixture(['customer' => 'cus_123']);
+        $this->assertSame(
+            "/v1/customers/cus_123/sources/" . self::TEST_RESOURCE_ID,
+            $resource->instanceUrl()
+        );
+    }
+
+    public function testHasCorrectUrlForAccount()
+    {
+        $resource = $this->createFixture(['account' => 'acct_123']);
+        $this->assertSame(
+            "/v1/accounts/acct_123/external_accounts/" . self::TEST_RESOURCE_ID,
+            $resource->instanceUrl()
+        );
+    }
+
+    /**
+     * @expectedException \Stripe\Error\InvalidRequest
+     */
+    public function testIsNotDirectlyRetrievable()
+    {
+        BankAccount::retrieve(self::TEST_RESOURCE_ID);
+    }
+
+    public function testIsSaveable()
+    {
+        $resource = $this->createFixture();
+        $resource->metadata["key"] = "value";
+        $this->expectsRequest(
+            'post',
+            '/v1/customers/cus_123/sources/' . self::TEST_RESOURCE_ID
+        );
+        $resource->save();
+        $this->assertSame("Stripe\\BankAccount", get_class($resource));
+    }
+
+    /**
+     * @expectedException \Stripe\Error\InvalidRequest
+     */
+    public function testIsNotDirectlyUpdatable()
+    {
+        BankAccount::update(self::TEST_RESOURCE_ID, [
+            "metadata" => ["key" => "value"],
         ]);
+    }
+
+    public function testIsDeletable()
+    {
+        $resource = $this->createFixture();
+        $this->expectsRequest(
+            'delete',
+            '/v1/customers/cus_123/sources/' . self::TEST_RESOURCE_ID
+        );
+        $resource->delete();
+        $this->assertSame("Stripe\\BankAccount", get_class($resource));
+    }
+
+    public function testIsVerifiable()
+    {
+        $resource = $this->createFixture();
         $this->expectsRequest(
             'post',
             '/v1/customers/cus_123/sources/' . self::TEST_RESOURCE_ID . "/verify",
diff --git a/tests/Stripe/BitcoinReceiverTest.php b/tests/Stripe/BitcoinReceiverTest.php
index b958b1e9d..cea999fc4 100644
--- a/tests/Stripe/BitcoinReceiverTest.php
+++ b/tests/Stripe/BitcoinReceiverTest.php
@@ -4,23 +4,59 @@
 
 class BitcoinReceiverTest extends TestCase
 {
-    public function testUrls()
+    const TEST_RESOURCE_ID = 'btcrcv_123';
+
+    // Because of the wildcard nature of sources, stripe-mock cannot currently
+    // reliably return sources of a given type, so we create a fixture manually
+    public function createFixture($params = [])
+    {
+        $base = [
+            'id' => self::TEST_RESOURCE_ID,
+            'object' => 'bitcoin_receiver',
+            'metadata' => [],
+        ];
+        return BitcoinReceiver::constructFrom(
+            array_merge($params, $base),
+            new Util\RequestOptions()
+        );
+    }
+
+    public function testHasCorrectStandaloneUrl()
+    {
+        $resource = $this->createFixture();
+        $this->assertSame(
+            "/v1/bitcoin/receivers/" . self::TEST_RESOURCE_ID,
+            $resource->instanceUrl()
+        );
+    }
+
+    public function testHasCorrectUrlForCustomer()
+    {
+        $resource = $this->createFixture(['customer' => 'cus_123']);
+        $this->assertSame(
+            "/v1/customers/cus_123/sources/" . self::TEST_RESOURCE_ID,
+            $resource->instanceUrl()
+        );
+    }
+
+    public function testIsListable()
     {
-        $classUrl = BitcoinReceiver::classUrl('Stripe_BitcoinReceiver');
-        $this->assertSame($classUrl, '/v1/bitcoin/receivers');
-        $receiver = new BitcoinReceiver('abcd/efgh');
-        $instanceUrl = $receiver->instanceUrl();
-        $this->assertSame($instanceUrl, '/v1/bitcoin/receivers/abcd%2Fefgh');
+        $this->expectsRequest(
+            'get',
+            '/v1/bitcoin/receivers'
+        );
+        $resources = BitcoinReceiver::all();
+        $this->assertTrue(is_array($resources->data));
+        $this->assertSame("Stripe\\BitcoinReceiver", get_class($resources->data[0]));
     }
 
-    //
-    // Note that there are no tests of consequences in here. The Bitcoin
-    // endpoints have been deprecated in favor of the generic sources API. The
-    // BitcoinReceiver class has been left in place for some backwards
-    // compatibility, but all users should be migrating off of it. The tests
-    // have been removed because we no longer have the API endpoints required
-    // to run them.
-    //
-    // [1] https://stripe.com/docs/sources
-    //
+    public function testIsRetrievable()
+    {
+        $this->expectsRequest(
+            'get',
+            '/v1/bitcoin/receivers/' . self::TEST_RESOURCE_ID
+        );
+        $resource = BitcoinReceiver::retrieve(self::TEST_RESOURCE_ID);
+        $this->assertSame("Stripe\\BitcoinReceiver", get_class($resource));
+    }
 }
diff --git a/tests/Stripe/CardTest.php b/tests/Stripe/CardTest.php
new file mode 100644
index 000000000..8976eff66
--- /dev/null
+++ b/tests/Stripe/CardTest.php
@@ -0,0 +1,94 @@
+<?php
+
+namespace Stripe;
+
+class CardTest extends TestCase
+{
+    const TEST_RESOURCE_ID = 'card_123';
+
+    // Because of the wildcard nature of sources, stripe-mock cannot currently
+    // reliably return sources of a given type, so we create a fixture manually
+    public function createFixture($params = [])
+    {
+        if (empty($params)) {
+            $params['customer'] = 'cus_123';
+        }
+        $base = [
+            'id' => self::TEST_RESOURCE_ID,
+            'object' => 'card',
+            'metadata' => [],
+        ];
+        return Card::constructFrom(
+            array_merge($params, $base),
+            new Util\RequestOptions()
+        );
+    }
+
+    public function testHasCorrectUrlForCustomer()
+    {
+        $resource = $this->createFixture(['customer' => 'cus_123']);
+        $this->assertSame(
+            "/v1/customers/cus_123/sources/" . self::TEST_RESOURCE_ID,
+            $resource->instanceUrl()
+        );
+    }
+
+    public function testHasCorrectUrlForAccount()
+    {
+        $resource = $this->createFixture(['account' => 'acct_123']);
+        $this->assertSame(
+            "/v1/accounts/acct_123/external_accounts/" . self::TEST_RESOURCE_ID,
+            $resource->instanceUrl()
+        );
+    }
+
+    public function testHasCorrectUrlForRecipient()
+    {
+        $resource = $this->createFixture(['recipient' => 'rp_123']);
+        $this->assertSame(
+            "/v1/recipients/rp_123/cards/" . self::TEST_RESOURCE_ID,
+            $resource->instanceUrl()
+        );
+    }
+
+    /**
+     * @expectedException \Stripe\Error\InvalidRequest
+     */
+    public function testIsNotDirectlyRetrievable()
+    {
+        Card::retrieve(self::TEST_RESOURCE_ID);
+    }
+
+    public function testIsSaveable()
+    {
+        $resource = $this->createFixture();
+        $resource->metadata["key"] = "value";
+        $this->expectsRequest(
+            'post',
+            '/v1/customers/cus_123/sources/' . self::TEST_RESOURCE_ID
+        );
+        $resource->save();
+        $this->assertSame("Stripe\\Card", get_class($resource));
+    }
+
+    /**
+     * @expectedException \Stripe\Error\InvalidRequest
+     */
+    public function testIsNotDirectlyUpdatable()
+    {
+        Card::update(self::TEST_RESOURCE_ID, [
+            "metadata" => ["key" => "value"],
+        ]);
+    }
+
+    public function testIsDeletable()
+    {
+        $resource = $this->createFixture();
+        $this->expectsRequest(
+            'delete',
+            '/v1/customers/cus_123/sources/' . self::TEST_RESOURCE_ID
+        );
+        $resource->delete();
+        $this->assertSame("Stripe\\Card", get_class($resource));
+    }
+}