| title | ISBN-13 (ISBN-10) | year of publica- tion | other author(s) |
|---|---|---|---|
| Functional Equations and Inequalities with Applications | 978-0-387-89491-1 (0-387-89491-8) | 2009 | |
| Introduction to Functional Equations | 978-1-4398-4111-2 (1-4398-4111-X) | 2011 | Prasanna K. Sahoo |