@book{43892,
	author = {Dummeier , Edwin F.  and Heflebower , Richard B. },
	title = {Economics With Applications To Agriculture /},
	publisher = {Mcgraw-hill Book Company,},
	year = {1940.},
	address = {New York :},
	edition = {Second Edition Sixth Impression},
	url = {https://fll.law.cu.edu.eg/fulltext/bks/B13-07728.pdf}
}