- Author: Albert Sweigart
- Language: English
- Year: 2015
- Author: Albert Sweigart
- Language: German
- Year: 2016
- Author: Albert Sweigart
- Language: English
- Year: 2015
- Author: Albert Sweigart
- Language: English
- Year: 2012
- Author: Albert Sweigart
- Language: English
- Year: 2010
- Author: Albert Sweigart
- Language: English