Bio-behavioural HIV and STI surveillance among men who have sex with men in Europe: the Sialon II protocols., Gios, Lorenzo, Mirandola Massimo, Toskin Igor, Ulrich Marcus, Dudareva-Vizule Sandra, Sherriff Nigel, Breveglieri Michele, Furegato Martina, Folch Cinta, Ferrer Laia, et al. , BMC Public Health, 2016 Mar 02, Volume 16, (2016)