| title | ISBN-13 | year of publica- tion | other author(s) |
|---|---|---|---|
| E-Z Spanish | 978-0-7641-4129-4 | 2009 | Ruth J. Silverstein · Heywood Wald Ph.D. |
| Spanish Now! Level 1 | 978-0-7641-2933-9 | 2005 | Ruth Silverstein · Haywood Wald Ph.D. |
| Spanish Now! Level 1 with CDs | 978-0-7641-7774-3 | 2005 | Ruth Silverstein · Haywood Wald Ph.D. |
| Spanish Now! Level 1: with MP3 CD | 978-1-4380-7523-5 | 2015 | Ruth Silverstein · Heywood Wald Ph.D. |
| Spanish the Easy Way | 978-0-7641-1974-3 | 2003 | Ruth J. Silverstein · Wald Heywood Ph.D |