- Author: Windsor Edward, Windsor Wallis Warfield, King Greg
- Language: English
- Year: 2011
- Author: Cockburn Bruce, King Greg
- Language: English
- Year: 2014
- Author: House of Habsburg, King Greg, Crown Prince of Austria Rudolf, Vetsera Mary, Wilson Penny
- Language: English
- Year: 2017
- Author: King Greg, Manson Charles, Tate Sharon
- Language: English
- Year: 2016
- Author: Heller Johnny, King Greg
- Language: English
- Year: 2015