THE EFFECT OF GROUP INVESTIGATION METHOD TOWARDS STUDENTS SPEAKING COMPETENCE BASED ON STUDENTS SELF-CONFIDENCE AT SMAN 1 SAKRA TIMUR IN ACADEMIC YEAR 2017/2018. JISIP (Jurnal Ilmu Sosial dan Pendidikan), [S. l.], v. 2, n. 3, 2018. DOI: 10.58258/jisip.v2i3.569. Disponível em: https://ejournal.mandalanursa.org/index.php/JISIP/article/view/569. Acesso em: 22 jun. 2026.