- Author: Hans Albert
- Language: Spanish
- Year: 2007
- Author: Eduardo Rivera López
- Language: Spanish
- Year: 1999
- Author: Roberto Gargarella
- Language: Spanish
- Year: 1997
- Author: Rodolfo Vázquez
- Language: Spanish
- Year: 1999
- Author: Josep M. Vilajosana
- Language: Spanish
- Year: 2005
- Author: Ernesto Abril
- Language: Spanish
- Year: 2004
- Author: Kaarlo Touri
- Language: Spanish
- Year: 2005
- Author: Martín Diego Farrell
- Language: Spanish
- Year: 1997
- Author: Paulette Dieterlen Struck
- Language: Spanish
- Year: 2001
- Author: Antonio Enrique Pérez Luño
- Language: Spanish
- Year: 2009