@article{Lang1996,
	title = {Efficiency and technical progress in banking Empirical results for a panel of German cooperative banks},
	author = {G{\"u}nter Lang and Peter Welzel},
	journal = {Journal of Banking \& Finance},
	month = {Jul},
	number = {6},
	pages = {1003--1023},
	url = {http://www.sciencedirect.com/science/article/B6VCY-3VW8P8B-3/1/2a92951c405ced1bebdb70466df61b5d},
	volume = {20},
	year = {1996},
	biburl = {http://www.bibsonomy.org/bibtex/2736692949f1dad4099dedd8c4bcf7588/smicha},
	description = {Journal of Banking & Finance},
	keywords = {Banking }
}