“Using Markov Chains to Establish the System of Reliability and Preventive Maintenance With Application Part”. Journal of Al-Rafidain University College For Sciences ( Print ISSN: 1681-6870 ,Online ISSN: 2790-2293 ) 46, no. 1 (October 1, 2021): 535–544. Accessed November 19, 2024. https://alhadhar.com/raf-journal/index.php/JAUCS/article/view/104.