| year of publication | ISBN | author(s) | title |
|---|---|---|---|
| 2006 | 978-0-9779614-0-5 | Ray Long | Scientific Keys Volume 1: The Key Muscles of Hatha Yoga by Ray Long (2006-04-20) |
| '' | 978-0-9779614-1-2 | Ray Long | The Key Muscles of Hatha Yoga (Scientific Keys) |
| 2008 | 978-0-9779614-2-9 | '' | Scientific Keys Vol. II: The Key Poses of Hatha Yoga |