| title | ISBN-13 | year of publica- tion | other author(s) | |
|---|---|---|---|---|
| 30 Minuten für professionelles Verhandeln | 978-3-930799-95-4 | 1999 | ||
| 30 Minutes to Negotiate a Better Deal | 978-0-7494-2666-8 | 1998 | ||
| Audissimo 30 Minuten für erfolgreiches Verhandeln. CD | 978-3-89749-522-7 | 2005 | Gisa Schmidt · Art Veder · Uwe Koschel | |
| How to Write a Business Plan | 978-0-7494-3590-5 | 2001 | ||
| How to Write a Business Plan (Creating Success) | 978-0-7494-4553-9 | 2006 | ||