The book "Concentration: Guide to Mental Mastery" by Mouni Sadhu is a vintage nonfiction guide to mental mastery originally published in 1973. Focused on the topic of meditation and spirituality, this paperback book is intended for adults and offers insight into the practices of yoga and philosophy. With 219 pages, this English language publication from the United States delves into the mind-body-spirit connection, making it a valuable resource for those seeking mental mastery and enlightenment in the 1950s era.