Rouwayda Nadhim Salih and Marwa Adeeb Al-jawaherry 2020. Finding Minimum and Maximum Values of Variables in Mathematical Equations by Applying Firefly and PSO Algorithm. Tikrit Journal of Pure Science. 25, 5 (Dec. 2020), 99–109. DOI:https://doi.org/10.25130/tjps.v25i5.298.