@techreport{NBERw12534,
 title = "Why Do U.S. Firms Hold So Much More Cash Than They Used To?",
 author = "Thomas W. Bates and Kathleen M. Kahle and Rene M. Stulz",
 institution = "National Bureau of Economic Research",
 type = "Working Paper",
 series = "Working Paper Series",
 number = "12534",
 year = "2006",
 month = "September",
 URL = "http://www.nber.org/papers/w12534",
}