@inbook{NBERc1526,
 Crossref = "NBERkrav66-1",
 title = "The Study of Comparative Prices",
 author = "Irving B. Kravis and Robert E. Lipsey",
 BookTitle = "Comparative Prices of Nonferrous Metals in International Trade, 1953-64",
 Publisher = "UMI",
 pages = "1-4",
 year = "1966",
 URL = "http://www.nber.org/chapters/c1526",
}
@book{NBERkrav66-1,
 title = "Comparative Prices of Nonferrous Metals in International Trade, 1953-64",
 author = "Irving B. Kravis and Robert E. Lipsey",
 institution = "National Bureau of Economic Research",
 type = "Book",
 publisher = "UMI",
 year = "1966",
 URL = "http://www.nber.org/books/krav66-1",
}