Islam, S. and Deb, S.C. 2020. Two-Echelon Supply Chain Model with Demand Dependent On Price, Promotional Effort and Service Level in Crisp and Fuzzy Environments. Pakistan Journal of Statistics and Operation Research. 16, 2 (Jun. 2020), 317-329. DOI:https://doi.org/10.18187/pjsor.v16i2.3091.