@inbook{NBERc4630,
 Crossref = "NBERdura57-1",
 title = "Appendix B: Some Problems Encountered in Classifying Bank Stocks into Groups",
 author = "David Durand",
 BookTitle = "Bank Stock Prices and the Bank Capital Problem",
 Publisher = "NBER",
 pages = "60-68",
 year = "1957",
 URL = "http://www.nber.org/chapters/c4630",
}
@book{NBERdura57-1,
 title = "Bank Stock Prices and the Bank Capital Problem",
 author = "David Durand",
 institution = "National Bureau of Economic Research",
 type = "Book",
 publisher = "NBER",
 year = "1957",
 URL = "http://www.nber.org/books/dura57-1",
}