I'm trying to put H.264 video with AAC audio in mp4 container.

I've read part 15 of the standard but I'm quite confused.

Which should I used for the sample description, AVCSampleEntry(avc1) or MP4VisualSampleSampleEntry(mp4v)?
avc1 is specified in part 15 but it don't have the elementry stream descriptor, I don't think this fits the MPEG4 system.

Many thanks.