C. Kamutthapichai, C. Kamutthapichai, W. Taweesup, and P. Aiemsai, “Cultural Capital of Kamphaeng Phet World Heritage Site and the Development of Creative Souvenir”, Humanities and Social Sciences Nakhonsawan Rajabhat University Academic Journal, vol. 13, no. 1, pp. 55–69, Jun. 2026.