diff --git a/tests/compat.sh b/tests/compat.sh
index 0a863fa..b914386 100755
--- a/tests/compat.sh
+++ b/tests/compat.sh
@@ -435,7 +435,8 @@
 # with its Mbed TLS name.
 #
 # NOTE: for some reason RSA-PSK doesn't work with OpenSSL,
-# so RSA-PSK ciphersuites need to go in other sections.
+# so RSA-PSK ciphersuites need to go in other sections, see
+# https://github.com/ARMmbed/mbedtls/issues/1419
 add_openssl_ciphersuites()
 {
     case $TYPE in