Novianti, Wina Kyky, and Sugiyono Sugiyono. “FACTORS CAUSING HISTORY TEACHERS’ DIFFICULTIES IN DEVELOPING INSTRUCTIONAL TEACHING IN SLEMAN REGENCY, YOGYAKARTA”. ISTORIA : Jurnal Pendidikan Dan Ilmu Sejarah, vol. 14, no. 2, Nov. 2018, doi:10.21831/istoria.v14i2.21919.