@inbook{NBERc8136,
 Crossref = "NBERunkn37-1",
 title = "Concepts of National Income",
 author = "M. A. Copeland",
 BookTitle = "Studies in Income and Wealth, Volume 1",
 Publisher = "NBER",
 pages = "2-63",
 year = "1937",
 URL = "http://www.nber.org/chapters/c8136",
}
@book{NBERunkn37-1,
 title = "Studies in Income and Wealth, Volume 1",
 author = "",
 institution = "National Bureau of Economic Research",
 type = "Book",
 publisher = "NBER",
 year = "1937",
 URL = "http://www.nber.org/books/unkn37-1",
}