@inbook{NBERc7271,
 Crossref = "NBERacem08-1",
 title = "Comment on "The Timing of Labor Market Expansions: New Facts and a New Hypothesis"",
 author = "Robert E. Hall",
 BookTitle = "NBER Macroeconomics Annual 2008, Volume 23",
 Publisher = "University of Chicago Press",
 pages = "53-58",
 year = "2009",
 month = "April",
 URL = "http://www.nber.org/chapters/c7271",
}
@book{NBERacem08-1,
 title = "NBER Macroeconomics Annual 2008, Volume 23",
 author = "Daron Acemoglu and Kenneth Rogoff and Michael Woodford",
 institution = "National Bureau of Economic Research",
 type = "Book",
 publisher = "University of Chicago Press",
 year = "2009",
 URL = "http://www.nber.org/books/acem08-1",
}