- Author: Sy Dux Raymond
- Language: English
- Year: 2008
- Author: Spalek Seweryn
- Language: English
- Year: 2019
- Author: Howard Eisner
- Language: English
- Year: 2011
- Author: Project Management Institute
- Language: English
- Year: 2013
- Author: Bevilacqua Alex
- Language: English
- Year: 2014
- Author: Bevilacqua Alex
- Language: English
- Year: 2014