Sirikasemsuk, Kittiwat, Tossapol Kiatcharoenpol, Hanoof Waiyaroop, Tadpon Kullawong, and Laksiri Treeranurat. 2021. “A Study of Factors Affecting The Screw Spacing of Spoilers in Hard Disk Drives for Productivity Increase Using Multiple Regression Analysis”. Naresuan University Engineering Journal 16 (1). Phitsanulok, Thailand:167-87. https://doi.org/10.14456/nuej.2021.15.