This book by Robert Mitchell Lindner, Jonathan Lear (intro) from the reviews this sounds like a classic – written in the 60’s. I was interested to hear in an Amazon review:
This book is particularly interesting in light of Gene Brewer’s novel (and now film) “K-PAX”, based on “The Jet-Propelled Couch” episode in this book.
I quite liked the film but not as much as the similar “Man Facing South East”.