@inbook{NBERc2364,
 Crossref = "NBERpote08-1",
 title = "Introduction to "Tax Policy and the Economy, Volume 22"",
 author = "James M. Poterba",
 BookTitle = "Tax Policy and the Economy, Volume 22",
 Publisher = "University of Chicago Press",
 pages = "1-3",
 year = "2008",
 month = "July",
 URL = "http://www.nber.org/chapters/c2364",
}
@book{NBERpote08-1,
 title = "Tax Policy and the Economy, Volume 22",
 author = "James M. Poterba",
 institution = "National Bureau of Economic Research",
 type = "Book",
 publisher = "University of Chicago Press",
 year = "2008",
 URL = "http://www.nber.org/books/pote08-1",
}