(1)
Sari, S. M.; Nasution, R. E.; Meidipa, L. F. An Analysis of Indefinite Pronouns Proficiency in English Sentences Among Seventh Grade Students at Madrasah Tsanawiah Yayasan Pendidikan Karya Setia (MTS YPKS) Padangsidimpuan. Journal ETANIC 2023, 1.