Bantam Books [1st paperback printing] - February 1970 (McKay hardcover was 1968.) Cover by Kossin, 214 pages, 95 cent cover price. Condition is VG+ or better: tight and almost square with flat spine, spine has 1 line and a raised wrinkle/ridge (as printed); age tanning is mild and uniform; very light overall wear. No stamps, marks or writing - a clean copy.

An uncommon novel by Martin Caidin: Four Came Back.
[from the back cover]: PROJECT EPSILON
It was an elaborate station 460 miles up in space. It wa manned by a team of the world's eight most brilliant scientists from five countries. Two of them were women. For months they lived, worked, played, and loved in orbit. They were an international family bound by more than conventional loyalty or the confines of the station. Theirs was a trip of classic excellence until two weeks before they were due to go home, when they hit a strange cloud of dust and decided to capture some for examination... FOUR CAME BACK.

Caidin tends to write near-future thrillers with good science. This means that time and events will tend to pass his novels by, and thus they will not get reprinted. I think that if the book is any good, this makes little difference - you will learn plenty about the fears and hopes of the time in which they were written.