diff --git a/doc/crypto_blake2b.3monocypher b/doc/crypto_blake2b.3monocypher
index 86ff25b..2dccb38 100644
--- a/doc/crypto_blake2b.3monocypher
+++ b/doc/crypto_blake2b.3monocypher
@@ -65,15 +65,15 @@
 .In monocypher.h
 .Ft void
 .Fo crypto_blake2b
-.Fa "uint8_t hash[64]"
+.Fa "uint8_t *hash"
 .Fa "size_t hash_size"
 .Fa "const uint8_t *message"
 .Fa "size_t message_size"
 .Fc
 .Fo crypto_blake2b_keyed
-.Fa "uint8_t hash[64]"
+.Fa "uint8_t *hash"
 .Fa "size_t hash_size"
-.Fa "uint8_t key[64]"
+.Fa "uint8_t *key"
 .Fa "size_t key_size"
 .Fa "const uint8_t *message"
 .Fa "size_t message_size"
@@ -87,7 +87,7 @@
 .Fo crypto_blake2b_keyed_init
 .Fa "crypto_blake2b_ctx *ctx"
 .Fa "size_t hash_size"
-.Fa "uint8_t key[64]"
+.Fa "uint8_t *key"
 .Fa "size_t key_size"
 .Fc
 .Ft void