- Author: Martín A. Litwak
- Language: Spanish, Castilian
- Year: 2018
- Author: Steve Sims
- Language: English
- Year: 2008
- Author: Swenson Charles W
- Language: English
- Year: 2004
- Author: Schnepper Jeff A
- Language: English
- Year: 2016
- Author: Pape Gordon
- Language: English
- Year: 2009
- Author: Pape Gordon
- Language: English
- Year: 2010
- Author: Fishman Stephen
- Language: English
- Year: 2006
- Author: J.K. Lasser Institute., Weltman Barbara
- Language: English
- Year: 2016
- Author: Scholes Myron S
- Language: English
- Year: 2015