Sari Adelina, Y., Neneng Sri Lestari, and E. Suprayetno. “Analysis Students Addition Error in Writing Thesis Abstract Of English Education Department STKIP AL Maksum Langkat”. JURNAL MUTIARA PENDIDIKAN INDONESIA, vol. 7, no. 2, Dec. 2022, pp. 167-72, doi:10.51544/mutiarapendidik.v7i2.3476.