@article{MacKellar2007,
author = {MacKellar, D.A. and Gallagher, K.M. and Finlayson, T. and Sanchez, T. and Lansky, A. and Sullivan, P.S.},
title= {Surveillance of HIV risk and prevention behaviors of men who have sex with men – A national application of venue-based, time-space sampling},
year = {2007},
journal = {Public Health Reports },
volume = {122},
number = {Suppl. 1},
pages = {39--47},
}