Five-year monitoring of a gay-friendly voluntary counselling and testing facility in Switzerland: who got tested and why? - Gumy, Cédric; Jeannin, André; Balthasar, Hugues; Huissoud, Thérèse; Jobin, Vincent; Häusermann, Michael; Crevoisier, Hubert; Sudre, Philippe; Dubois-Arber, Françoise (BMC Public Health, 2012)