R. N. V. Susanto, H. F. Kholis, and R. F. Adtya, “Problem and Project Based Questions in the Indonesian Language Book for Grade XI Published by Erlangga: Muatan Soal Berbasis Problem dan Project pada Butir Soal Buku Bahasa Indonesia Kelas XI Terbitan Erlangga”, RDT, vol. 5, no. 3, pp. 226-240, Jan. 2025.