@article {14086928, title = {{A clone-based graphical modeler and mathematical model generator for optimal production planning in process industries}}, journal = {European Journal of Operational Research}, volume = {137}, year = {2002}, pages = {483{\textendash}496}, doi = {10.1016/S0377-2217(01)00066-2}, author = {Murat Draman and I. Kuban Altinel and Nijaz Bajgoric and Ali Tamer {\"U}nal and Burak Birg{\"o}ren} }