diff --git a/doc/crypto/err.pod b/doc/crypto/err.pod
index 5b0c4698c..029899769 100644
--- a/doc/crypto/err.pod
+++ b/doc/crypto/err.pod
@@ -116,6 +116,8 @@ ERR_get_string_table(void) respectively.
 
 =head1 SEE ALSO
 
+L<CRYPTO_set_id_callback(3)|CRYPTO_set_id_callback(3)>,
+L<CRYPTO_set_locking_callback(3)|<CRYPTO_set_locking_callback(3)>,
 L<ERR_get_error(3)|ERR_get_error(3)>,
 L<ERR_GET_LIB(3)|ERR_GET_LIB(3)>,
 L<ERR_clear_error(3)|ERR_clear_error(3)>,