The UN Treaty Body References to sexual orientation, gender identity, gender expression, and sex characteristics (2015)  was written and researched by Helen Nolan, and published by ILGA. The document is available for download here.

It is copyright-free provided you cite both the author and the International Lesbian, Gay, Bisexual, Trans and Intersex Association (ILGA).
Suggested citation: International Lesbian, Gay, Bisexual, Trans and Intersex Association: Nolan H, United Nations Treaty Bodies: References to sexual orientation, gender identity,
gender expression and sex characteristics 2015 (Geneva: ILGA, September 2016)