@techreport{NBERw13749,
 title = "Inflation-Gap Persistence in the U.S.",
 author = "Timothy Cogley and Giorgio E. Primiceri and Thomas J. Sargent",
 institution = "National Bureau of Economic Research",
 type = "Working Paper",
 series = "Working Paper Series",
 number = "13749",
 year = "2008",
 month = "January",
 URL = "http://www.nber.org/papers/w13749",
}