@inbook{NBERc10516,
 Crossref = "NBERaesm77-2",
 title = "The Allocation of a Natural Resource When the Cost of a Substitute Is Uncertain",
 author = "Donald Hanson",
 BookTitle = "Annals of Economic and Social Measurement, Volume 6, number 2",
 Publisher = "NBER",
 pages = "189-201",
 year = "1977",
 month = "April",
 URL = "http://www.nber.org/chapters/c10516",
}
@book{NBERaesm77-2,
 title = "Annals of Economic and Social Measurement, Volume 6, number 2",
 author = "Sanford V. Berg, editor",
 institution = "National Bureau of Economic Research",
 type = "Book",
 publisher = "NBER",
 year = "1977",
 URL = "http://www.nber.org/books/aesm77-2",
}