@book{352455,
	author = {Cohen, Deborah A.;Sturm, Roland;Han, Bing;Marsh, Terry},
	title = {Quantifying the Contribution of Public Parks to Physical Activity and Health},
	publisher = {RAND Corporation},
	year = {2014},
	url = {http://www.jstor.org/stable/10.7249/j.ctt14bs3fd}
}