Ruth Monika Simanjuntak, Nadya Bersista E Marbun, Mutiara Rajagukguk, and Anita Sitanggang. “A Contrastive Analysis Of Interrogative Sentences In English and Indonesian”. Jurnal Ilmu Pendidikan Dan Sosial, vol. 2, no. 2, Aug. 2023, pp. 221-30, doi:10.58540/jipsi.v2i2.382.