@inbook{NBERc10570,
 Crossref = "NBERpote08-3",
 title = "New Evidence on the Labor Supply Effects of the Social Security Earnings Test ",
 author = "Leora Friedberg and Anthony Webb",
 BookTitle = "Tax Policy and the Economy, Volume 23",
 Publisher = "University of Chicago Press",
 pages = "1-35",
 year = "2009",
 month = "July",
 URL = "http://www.nber.org/chapters/c10570",
}
@book{NBERpote08-3,
 title = "Tax Policy and the Economy, Volume 23",
 author = "Jeffrey R. Brown and James M. Poterba",
 institution = "National Bureau of Economic Research",
 type = "Book",
 publisher = "University of Chicago Press",
 year = "2009",
 URL = "http://www.nber.org/books/pote08-3",
}