- Author: Ralf Rother
- Language: German
- Year: 2006
- Author: Vereinte Nationen., Gray Christine D
- Language: English
- Year: 2009
- Author: West Alexandra
- Language: English
- Year: 2016
- Author: West Alexandra
- Language: English
- Year: 2016
- Author: Richards Stephen C., Ross Jeffrey Ian
- Language: English
- Year: 2002
- Author: Phillips Nickie D
- Language: English
- Year: 2017
- Author: Pansters Wil G., Smith Benjamin T., Watt Peter
- Language: English
- Year: 2018
- Author: Wallace Michael, Hofstadter Richard
- Language: English
- Year: 1970
- Author: Wallace Michael, Hofstadter Richard
- Language: English
- Year: 1970
- Author: North Douglass Cecil, Wallis John Joseph, Weingast Barry R
- Language: English
- Year: 2013