diff --git a/other-notations/YARSpg.ebnf b/other-notations/YARSpg.ebnf
index d6c4d77..f504ee6 100644
--- a/other-notations/YARSpg.ebnf
+++ b/other-notations/YARSpg.ebnf
@@ -53,7 +53,7 @@ annotation
          ::= string_annotation
            | rdf_annotation
 string_annotation
-         ::= STRING ':' STRING
+         ::= key ':' STRING
 rdf_annotation
          ::= ((pn_local pname) | (IRI ':')) (STRING | IRI)
 annotations_list
diff --git a/yarspg/YARSpg.g4 b/yarspg/YARSpg.g4
index 6e4b714..83f386e 100644
--- a/yarspg/YARSpg.g4
+++ b/yarspg/YARSpg.g4
@@ -66,7 +66,7 @@ annotation
     ;
 
 string_annotation
-    : STRING ':' STRING
+    : key ':' STRING
     ;
 
 rdf_annotation