| title | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|
| Access Control Systems | 978-81-8128-910-0 (81-8128-910-2) | 2008 |
| Access Control Systems: Security, Identity Management and Trust Models | 978-0-387-00445-7 (0-387-00445-9) | 2005 |
| Introduction to the Public Key Infrastructure for the Internet | 978-0-13-060927-4 (0-13-060927-7) | 2001 |