- Author: Elke Stein-Hölkeskamp, Karl-Joachim Hölkeskamp
- Language: German
- Year: 2019
- Author: Mark Schiefer, Karl-Joachim Hölkeskamp
- Language: German
- Year: 2018
- Author: Karl-J. Hölkeskamp, Henry Heitmann-Gordon
- Language: English
- Year: 2010
- Author: Karl-Joachim Hölkeskamp, Sema Karataş, Roman Roth
- Language: English
- Year: 2019
- Author: Karl-Joachim Hölkeskamp
- Language: Spanish
- Year: 2019
- Author: Karl-Joachim Hölkeskamp
- Language: German
- Year: 2004