Daniel Ganda Putra Sihombing, David Togi Hutahaean, Yanti kristina Sinaga, Tiarma Intan Marpaung and Anita Sitanggang 2023. The Effect Of Reinforcement On Writing Skill At Eleventh Grade Students In SMK Negeri 1 Pematang Siantar . Jurnal Ilmu Pendidikan dan Sosial. 2, 3 (Oct. 2023), 381–389. DOI:https://doi.org/10.58540/jipsi.v2i3.447.