Samsir, A. U., Toaha, S. ., & Kasbawati, K. (2021). Optimal Control of a Mathematical Model of Smoking with Temporary Quitters and Permanent Quitters. Jurnal Matematika, Statistika Dan Komputasi, 18(1), 42–54. https://doi.org/10.20956/j.v18i1.13974