Prabhath Perera, Polpithige Chaya, Yaowarat Sriwaranun, และ Patcharee Suriya. 2019. “Consumers’ Willingness to Pay for Liquid Milk in Sri Lanka”. วารสารแก่นเกษตร 47 (4):851-63. https://li01.tci-thaijo.org/index.php/agkasetkaj/article/view/249905.