Ellok Rini Widyaning (2019) “Analisis Kesalahan Menyelesaikan Soal Cerita Siswa Kelas VIII Materi Sistem Persamaan Linier Dua Variabel di SMP PGRI Sumobito”, Journal Focus Action of Research Mathematic (Factor M), 2(1), pp. 1–14. doi: 10.30762/factor_m.v2i1.1682.