This is a collection of short stories published in 1959 that I listened to as an audiobook.
I found these stories to be kind of slow and mediocre. Maybe if I had listened to them in 1959 my opinion would be very different, but listening to them now they do not come across like they were written by a writer as great as Robert Heinlein.
If you are a time travel fan the story “By His Bootstraps” is a must read.
I recommend this book only to Heinlein fans and rate it a 4 out of 10.