Suratmi, S. “Implementation Of Individual Guidance Through Whatsapp Group To Increase Achievement And Learning Motivation Of Students Of Class VII SMP Negeri 3 Ngaglik Sleman 2020/2021”. IJCER (International Journal of Chemistry Education Research), vol. 5, no. 2, Oct. 2021, pp. 97-104, doi:10.20885/ijcer.vol5.iss2.art8.