Mardlijah, M. et al. 2018. Optimal Control of Lipid Extraction Model on Microalgae Using Linear Quadratic Regulator (LQR) and Pontryagin Maximum Principle (PMP) Methods. MATEMATIKA. 34, 3 (Dec. 2018), 129–140. DOI:https://doi.org/10.11113/matematika.v34.n3.1145.