@inbook{NBERc2212,
 Crossref = "NBERkarr61-1",
 title = "Methods to Correct Freight Payments",
 author = "Herman F. Karreman",
 BookTitle = "Methods for Improving World Transportation Accounts, Applied to 1950-1953",
 Publisher = "NBER",
 pages = "64-73",
 year = "1961",
 URL = "http://www.nber.org/chapters/c2212",
}
@book{NBERkarr61-1,
 title = "Methods for Improving World Transportation Accounts, Applied to 1950-1953",
 author = "Herman F. Karreman",
 institution = "National Bureau of Economic Research",
 type = "Book",
 publisher = "NBER",
 year = "1961",
 URL = "http://www.nber.org/books/karr61-1",
}