@inbook{NBERc10710,
 Crossref = "NBERgrub04-1",
 title = "The Effect of Social Security on Retirement in the United States",
 author = "Courtney Coile and Jonathan Gruber",
 BookTitle = "Social Security Programs and Retirement around the World: Micro-Estimation",
 Publisher = "University of Chicago Press",
 pages = "691-730",
 year = "2004",
 month = "January",
 URL = "http://www.nber.org/chapters/c10710",
}
@book{NBERgrub04-1,
 title = "Social Security Programs and Retirement around the World: Micro-Estimation",
 author = "Jonathan Gruber and David A. Wise",
 institution = "National Bureau of Economic Research",
 type = "Book",
 publisher = "University of Chicago Press",
 year = "2004",
 URL = "http://www.nber.org/books/grub04-1",
}