Ahmad, Mahdi, and S Sukariman. 2018. “The Influence of English Teacher Certification and Non-Certification towards the Students’ Understanding on English Grammar at SMAN 4 Halmahera Barat and at SMAN 3 Kota Ternate”. Langua: Journal of Linguistics, Literature, and Language Education 1 (1), 83-97. https://doi.org/10.5281/zenodo.1443469.