- Author: Emilio Gentile
- Language: Italian
- Year: 2007
- Author: Titus Burckhardt
- Language: Italian
- Year: 2004
- Author: Soneira Begoña
- Language: English
- Year: 2015
- Author: Wallenstein Sven-Olov
- Language: English
- Year: 2009
- Author: Carpo Mario
- Language: English
- Year: 2017
- Author: Hennessy John L., Patterson David A
- Language: English
- Year: 2019
- Author: John Ruskin
- Language: Italian
- Year: 2007
- Author: Graham Stephen
- Language: English
- Year: 2016
