diff --git a/internal/fmtp/av1.go b/internal/fmtp/av1.go
index 59d8b31a8d1..29eccd114d0 100644
--- a/internal/fmtp/av1.go
+++ b/internal/fmtp/av1.go
@@ -17,7 +17,8 @@ func (h *av1FMTP) Match(b FMTP) bool {
 		return false
 	}
 
-	// AV1 RTP specification:
+	// RTP Payload Format For AV1 (v1.0)
+	// https://aomediacodec.github.io/av1-rtp-spec/
 	// If the profile parameter is not present, it MUST be inferred to be 0 (“Main” profile).
 	hProfile, ok := h.parameters["profile"]
 	if !ok {
diff --git a/internal/fmtp/vp9.go b/internal/fmtp/vp9.go
index 9400fe02b6f..7fc618bccd8 100644
--- a/internal/fmtp/vp9.go
+++ b/internal/fmtp/vp9.go
@@ -17,7 +17,8 @@ func (h *vp9FMTP) Match(b FMTP) bool {
 		return false
 	}
 
-	// draft-ietf-payload-vp9-16:
+	// RTP Payload Format for VP9 Video - draft-ietf-payload-vp9-16
+	// https://datatracker.ietf.org/doc/html/draft-ietf-payload-vp9-16
 	// If no profile-id is present, Profile 0 MUST be inferred
 	hProfileID, ok := h.parameters["profile-id"]
 	if !ok {