Nguyen และ Thanh Son. (1998) Premarital sexual behavior among single male students aged 17-24 in Hanoi and Ho Chi Minh City of Vietnam. Mahidol University,:ม.ป.ท.Nguyen และ Thanh Son. 1998. Premarital sexual behavior among single male students aged 17-24 in Hanoi and Ho Chi Minh City of Vietnam. ม.ป.ท.:Mahidol University,;Nguyen และ Thanh Son. Premarital sexual behavior among single male students aged 17-24 in Hanoi and Ho Chi Minh City of Vietnam. ม.ป.ท.:Mahidol University, 1998. Print.