“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”. 2018. JISIP (Jurnal Ilmu Sosial Dan Pendidikan) 2 (3). https://doi.org/10.58258/jisip.v2i3.569.