| year of publication | ISBN | author(s) | title |
|---|---|---|---|
| 1979 | 978-0-906632-00-0 | J. C. Wells · etc. | Jen Nia Mondo: Bk. 1 |
| '' | 978-0-906632-01-7 | J.C. Wells · etc. | Jen Nia Mondo: Bk. 2 |
| 1985 | 978-0-906632-02-4 | J. C. Wells | Geiriadur Esperanto: Kimra Vortaro |
| 2005 | 978-0-906632-05-5 | John Wells | Jen Nia Mondo 2 |
| '' | 978-0-906632-06-2 | John C. Wells | Jen Nia Mondo: Bk. 1: The Complete Course in Esperanto, the International Language |