Chainawakul, A., Sangkas, T., Kamthai, S. and Manokruang, S. (2025) “Reducing Sink Mark Defect of Cup Plastic Injection by Biodegradable Material with an Injection Rate”, RMUTL Engineering Journal, 10(1), pp. 27–34. doi: 10.14456/rmutlengj.2025.4.