Effectiveness of community outreach HIV prevention programs in Vietnam: a mixed methods evaluation oleh Lora L. Sabin, Katherine Semrau, Mary DeSilva, Loan T T Le, Jennifer J. Beard, Davidson H. Hamer, Jordan Tuchman, Theodore M. Hammett, Nafisa Halim, Manisha Reuben, Aldina Mesic, Taryn Vian