Oke, S.A., and O.E. Charles-Owaba. “A Fuzzy Linguistic Approach of Preventive Maintenance Scheduling Cost Optimisation”. Kathmandu University Journal of Science, Engineering and Technology 3, no. 1 (January 31, 2007). Accessed November 24, 2024. https://nepjol.info./index.php/KUSET/article/view/64178.