@inbook{NBERc2333,
 Crossref = "NBERfrie54-1",
 title = "Appendix A: The Reliability of the Department of Commerce Samples",
 author = "Milton Friedman and Simon Kuznets",
 BookTitle = "Income from Independent Professional Practice",
 Publisher = "NBER",
 pages = "411-488",
 year = "1954",
 URL = "http://www.nber.org/chapters/c2333",
}
@book{NBERfrie54-1,
 title = "Income from Independent Professional Practice",
 author = "Milton Friedman and Simon Kuznets",
 institution = "National Bureau of Economic Research",
 type = "Book",
 publisher = "NBER",
 year = "1954",
 URL = "http://www.nber.org/books/frie54-1",
}