Fadhila N, Wastuti SNY, Astuti S. THE APPLICATION OF PROBLEM-BASED LEARNING TECHNIQUES IN CLASSICAL SERVICES TO INCREASE SELF-CONFIDENCE. Algebra JPSS [Internet]. 2025 May 31 [cited 2026 Apr. 19];5(2):226-32. Available from: https://ejournal.yana.or.id/index.php/algebra/article/view/1267