Goode, Stephen. «The fact and fiction of America's outlaw». The Washington Times, 10-06-2007. Arxivat de l'original el 20 juny 2009. [Consulta: 25 desembre 2015]. «Billy loved to sing and had a good voice, those who knew him claimed ... He was ambidextrous and wrote well with both hands.»
Goode, Stephen. «The fact and fiction of America's outlaw». The Washington Times, 10-06-2007. Arxivat de l'original el 20 juny 2009. [Consulta: 25 desembre 2015]. «Billy loved to sing and had a good voice, those who knew him claimed ... He was ambidextrous and wrote well with both hands.»