| year of publication | ISBN | author(s) | title |
|---|---|---|---|
| 1993 | 978-0-9707531-0-6 | Bill J. Bonnstetter · Judy I. Suiter · Randy J. Widrick | The Universal Language DISC |
| 2007 | 978-0-9707531-1-3 | Bill J. Bonnstetter · Judy Suiter | The Universal Language DISC: A Reference Manual |
| 2013 | 978-0-9707531-3-7 | Bill J. Bonnstetter, Ronald Bonnstetter Eduard Spranger | Types of Men |