| title | ISBN-13 (ISBN-10) | year of publica- tion | other author(s) |
|---|---|---|---|
| 21st Century Dictionary of Quotations | 978-0-440-21447-2 (0-440-21447-5) | 1993 | |
| 21st Century Dictionary of Slang | 978-0-440-21551-6 (0-440-21551-X) | 1994 | |
| 21st Century Robert's Rules of Order | 978-0-440-21722-0 (0-440-21722-9) | 1995 | Laurie E. Rozakis · Ellen Lichtenstein |