diff --git a/index.bs b/index.bs
index f6d548a4..2128a3df 100644
--- a/index.bs
+++ b/index.bs
@@ -37,6 +37,9 @@ url: https://www.iso.org/standard/83102.html#; spec: ISO-BMFF; type: property;
 	text: ctts
 	text: stss
 	text: btrt
+	text: mdhd
+	text: elng
+
 
 url: https://aomediacodec.github.io/av1-spec/av1-spec.pdf#; spec: AV1-Spec; type: dfn;
 	text: Clip3