Supriyadi, Dikdik. “Principal Procurement Policy Analysis in Achieving School Management Excellence”. International Journal of Management Excellence (ISSN: 2292-1648) 11, no. 3 (October 31, 2018): 1672–1679. Accessed October 13, 2025. https://techmindresearch.org/index.php/ijme/article/view/1036.