@inbook{NBERc9077,
 Crossref = "NBERgort76-1",
 title = "Concentration and Profit Rates: New Evidence on an Old Issue",
 author = "Michael Gort and Rao Singamsetti",
 BookTitle = "Explorations in Economic Research, Volume 3, number 1",
 Publisher = "NBER",
 pages = "1-20",
 year = "1976",
 URL = "http://www.nber.org/chapters/c9077",
}
@book{NBERgort76-1,
 title = "Explorations in Economic Research, Volume 3, number 1",
 author = "NBER",
 institution = "National Bureau of Economic Research",
 type = "Book",
 publisher = "NBER",
 year = "1976",
 URL = "http://www.nber.org/books/gort76-1",
}