Charoenchai Agmapisarn. (2010) Willingness to Pay for a Free HIV Vaccination Programme. <i>NIDA Development Journal</i>, <i>50</i>(2), 129-151.Charoenchai Agmapisarn. "Willingness to Pay for a Free HIV Vaccination Programme". NIDA Development Journal 50 (2010):129-151.Charoenchai Agmapisarn. Willingness to Pay for a Free HIV Vaccination Programme. National Institute of Development Administration:ม.ป.ท. 2010.