Sangwalee, wararat, J. Norkaew, M. Photipim, V. Ketbumroong, J. Prathumyo, T. Udomporn, P. Naunklang, S. Inthachak, and W. Sangwalee. “Factors Associate Preventive Behaviors of Unplanned Pregnancy Among the Female Vocational Students in Nakhon Ratchasima Province”. Journal of Vongchavalitkul University, vol. 34, no. 1, June 2021, pp. 34-46, https://ph01.tci-thaijo.org/index.php/vujournal/article/view/244212.