http://www.genomicseducation.ca/educationresources/young_scientists/floyd_questions/xyy_men.asphttp://www.genomicseducation.ca/educationresources/young_scientists/floyd_questions/xyy_men.asp

https://rarediseases.org/rare-diseases/xyy-syndrome/https://rarediseases.org/rare-diseases/xyy-syndrome/

http://www.rarechromo.org/information/Chromosome_Y/XYY%20FTNW.pdf