Anyway, as noted above, William A. Anthony's The Art of Napping is a very silly book. He claims to have taken six years to write this slim volume, which I guess must be a testament of some sort to his expertise with naps. I found his "technical jargon" (nap-thisology, nap-thatism, etc.) as insufferable as it was inescapable, but there were some informational nuggets that were of interest (for instance, the days following Daylight Savings switch-overs have a statistical increase or decrease in traffic accidents, 7% more than normal on the days following "losing" an hour and 7% less than normal on the days following "gaining" and hour).
The author of The Art of Napping is a psychology professor at Boston University, and I found myself deeply hoping that his various "Nap crusades" pressed in the book were presented with tongue firmly in cheek. Sure, I like napping as much as the next guy, but I'd hate to see Government Departments enforcing "nap breaks" on businesses nationwide! If you really feel a need to read up on napping, this is both still in print, and available via Amazon's new/used for a few bucks. Personally, I don't seek out humor books, so this is "not my thing", but (in the words of Johnny Carson) "It takes all types to fill the freeway", so you might find this to be to your liking.