- Author: Gerhard Matzig Christian Schittich Peter Cachola Schmal
- Language: German
- Year: 2011
- Author: Christian Schittich
- Language: English
- Year: 2003
- Author: Christian Schittich
- Language: French
- Year: 2006
- Author: Christian Schittich
- Language: English
- Year: 2001
- Author: Christian Schittich Gerald Staib Dieter Balkow Matthias Schuler Werner Sobek
- Language: English
- Year: 1999