Laksitanon, R., S. Suthusvoravut, S. Patrachai, and V. Singhakajen. “Factors Associated with Sexual Relationship Among High School Female Students in Ratchaburi Province”. Research Medical Journal, vol. 33, no. 2, June 2010, pp. 70-78, https://he02.tci-thaijo.org/index.php/ramajournal/article/view/138398.