@inbook{NBERc0831,
 Crossref = "NBERcope52-1",
 title = "Moneyflows and Commodity Flows",
 author = "Morris A. Copeland",
 BookTitle = "A Study of Moneyflows in the United States",
 Publisher = "NBER",
 pages = "85-97",
 year = "1952",
 URL = "http://www.nber.org/chapters/c0831",
}
@book{NBERcope52-1,
 title = "A Study of Moneyflows in the United States",
 author = "Morris A. Copeland",
 institution = "National Bureau of Economic Research",
 type = "Book",
 publisher = "NBER",
 year = "1952",
 URL = "http://www.nber.org/books/cope52-1",
}