Kongroy, Porntawee, Thanawan Pinawet, and Kankulnat Peerachaakkarachai. “Development and Upgrading of Organic Fertilizer Products Using Circular Economy Concept to Empower the Na Ngua Organic Agriculture Group, Phetchabun Province”. The Golden Teak : Science and Technology Journal (GTSJ.) 13, no. 1 (August 28, 2026): 38–55. accessed September 13, 2026. https://li02.tci-thaijo.org/index.php/gts/article/view/2053.