Hilapad, Marife R., and Roberta D. Lauzon. 2015. “Formulation and Optimization of Herb-Flavored Sweetpotato-Chocolate Spread”. International Research Journal on Innovations in Engineering, Science and Technology 1 (1):26-33. https://ojs.batstate-u.edu.ph/index.php/IRJIEST/article/view/9.