Yusra T, Purwanto E, Awalya A. The Effectiveness of Classroom Guidance with Problem-based Learning and Jigsaw Techniques to Improve Negative Attitudes towards Premarital Sexual Behavior. JUBK [Internet]. 21Jan.2020 [cited 21Dec.2024];9(1):7-2. Available from: https://journal.unnes.ac.id/sju/jubk/article/view/34629