*, F. and Wahyuni, Y. 2017. THE STUDY OF STUDENTS’ DIFFICULTY IN OPERATING OBE THROUGH TPS METHOD: A CASE STUDY OF ALE (ELEMENTARY LINEAR ALGEBRA) COURSE. IJRDO- Journal of Educational Research. 2, 4 (Apr. 2017), 111-115. DOI:https://doi.org/10.53555/er.v2i4.186.