Clinton Ober, Stephen T. Sinatra , Martin Zucker Ober · O's · Ober Scot · S. Ober
| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| Soft World: A Typing Practice Set | 978-0-07-048037-7 (0-07-048037-0) | 1987 |
| Typing Softworld: Teacher's Manual | 978-0-07-048038-4 (0-07-048038-9) | 1987 |