- Author: John C. Hull, Almut Oetjen, Holger Wacker
- Language: German
- Year: 2001
- Author: Richard P. Bagozzi, José Antonio Rosa, Kirstin Sawhney Celly, Francisco Coronel, Almut Oetjen, Holger Wacker, Hendrik Voß
- Language: German
- Year: 2000
- Author: Michael D. Johnson, Almut Oetjen, Oliver de Byl, Hendrik Voß, Holger Wacker
- Language: German
- Year: 2001
- Author: Holger Wacker, Jürgen E. Blank
- Language: German
- Year: 1998
- Author: David L. Scott, Almut Oetjen, Ulrich Scheele, Holger Wacker
- Language: German
- Year: 2000
- Author: Holger Wacker, Jürgen Blank
- Language: German
- Year: 1999
- Author: Holger Wacker Frank Baeseler
- Language: German