Too Many Heavens: On Travelogues to the Great Beyond
Here is the first book of some people who saw heaven that I ever read (Free on~line copy). I found it at a Catholic Bookstore in Costa Mesa California called "Sacred Heart Treasure House." The first Christian oriented book store that I Could find back in 1967, Christianity had not been commercialized yet.
The kids in the book were Chinese and had never heard of Jesus Christ so their accounts of heaven were more reliable it would seem.