@inbook{NBERc6228,
 Crossref = "NBERfeld91-2",
 title = "Introduction to "The Risk of Economic Crisis"",
 author = "Martin Feldstein",
 BookTitle = "The Risk of Economic Crisis",
 Publisher = "University of Chicago Press",
 pages = "1-18",
 year = "1991",
 month = "January",
 URL = "http://www.nber.org/chapters/c6228",
}
@book{NBERfeld91-2,
 title = "The Risk of Economic Crisis",
 author = "Martin Feldstein",
 institution = "National Bureau of Economic Research",
 type = "Book",
 publisher = "University of Chicago Press",
 year = "1991",
 URL = "http://www.nber.org/books/feld91-2",
}