this is one of my favorite series by burroughs and here is my reading list for john carter of mars:
and here are two that were written by his son
john carter and the giant of mars
skeleton men of Jupiter
I'm not an ERB expert, but I think he actually wrote "Skeleton Men." It was only "Giant" that was written in part by his son. It's been years since I've read them, but, as I recall, "Skeleton Men" read just the other books.