diff --git a/crypto-primitives/src/sponge/mod.rs b/crypto-primitives/src/sponge/mod.rs
index 19baba8..b3e270b 100644
--- a/crypto-primitives/src/sponge/mod.rs
+++ b/crypto-primitives/src/sponge/mod.rs
@@ -17,9 +17,9 @@ pub use absorb::*;
 /// [cos]: https://eprint.iacr.org/2019/1076
 pub mod poseidon;
 
-/// The sponge for Merlin
-///
+/// The sponge for [Merlin][merlin]
 ///
+/// [merlin]: https://merlin.cool/
 pub mod merlin;
 
 #[cfg(test)]