Achterbergh, R., Drückler, S., Van Rooijen, M., Van Aar, Slurink, I., De Vries, J., Boyd, A. (2020). Sex, drugs, and sexually transmitted infections: A latent class analysis among men who have sex with men in Amsterdam and surrounding urban regions, the Netherlands. Drug and Alcohol Dependence, 206(1). https://doi.org/10.1016/j.drugalcdep.2019.06.028