Seangpraw, K., and V. Sresumatchai. “Knowledge, attitude, perceived self-efficacy and behavior related to sexual risk behavior among university students in North Thailand”. Journal of Health Research, vol. 30, no. 2, Feb. 2017, pp. 127-34, https://he01.tci-thaijo.org/index.php/jhealthres/article/view/77944.