@article {1472,
	title = {A multi echelon inventory system with returns},
	journal = {Computers \& Industrial Engineering},
	volume = {35},
	year = {1998},
	month = {Oct},
	pages = {145{\textendash}148},
	issn = {03608352},
	author = {Aybek Korugan and Gupta, Surendra M}
}
