Sutha .M, Sridhar. A. “Univariate Maintenance Model for a Deteriorating System under Two Monotone Processes”. Mathematical Statistician and Engineering Applications 71, no. 4 (September 8, 2022): 2044–2054. Accessed April 29, 2024. https://www.philstat.org/index.php/MSEA/article/view/746.