Scholz, Stefan Michael ; Damm, Oliver ; Elkenkamp, Svenja... https://researchonline.lshtm.ac.uk/id/eprint/4657835/1/Population%20size%20and%20self-reported%20characteristics%20and%20sexual%20preferences%20of%20men-who-have-sex-with-men%20%28MSM%29%20in%20Germany%20based.pdf.
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2019