@book{53868,
	author = {Nas, Steve. and Gala, Deepak M. and Society of Petroleum Engineers (U.S.)},
	title = {Underbalanced drilling},
	publisher = {Society of Petroleum Engineers,},
	year = {c2012.},
	series = {Getting up to speed},
	address = {Richardson, TX :},
	url = {http://site.ebrary.com/lib/rucke/Doc?id=10619571}
}