Kittichotipun, Yingkwan, and Sawanya Thamma-apipon. 2020. “Guidelines for Communication Process in Enhancing Purchasing Efficiency: A Case Study of Beverage Manufacturer in Nakhonpathom Province”. Journal of Innovation and Management 5 (-):71-84. https://so03.tci-thaijo.org/index.php/journalcim/article/view/246775.