@inbook{NBERc3901,
 Crossref = "NBERzell79-1",
 title = "SABL: A Resistant Seasonal Adjustment Procedure with Graphical Methods for Interpretation and Diagnosis",
 author = "William S. Cleveland and Douglas M. Dunn and Irma J. Terpenning",
 BookTitle = "Seasonal Analysis of Economic Time Series",
 Publisher = "NBER",
 pages = "201-241",
 year = "1979",
 URL = "http://www.nber.org/chapters/c3901",
}
@book{NBERzell79-1,
 title = "Seasonal Analysis of Economic Time Series",
 author = "Arnold Zellner",
 institution = "National Bureau of Economic Research",
 type = "Book",
 publisher = "NBER",
 year = "1979",
 URL = "http://www.nber.org/books/zell79-1",
}