Putri, I.; Widayati, W.; Tobing, V. M. T. Pemerolehan Kosakata Anak Down Syndrome Berdasarkan Kelas Kata Bahasa Indonesia Di SLB C1 AKW Kumara 1 Surabaya: The Acquisition of Vocabulary in Down Syndrome Children Based on Word Classes in Indonesian Language at C1 AKW Kumara 1 Special School Surabaya. Jubasan 2020, 4, 22-28.