@inbook{NBERc9729, Crossref = "NBERfeen03-1", title = "Price Collection and Quality Assurance of Item Sampling in the Retail Prices Index.How Can Scanner Data Help? ", author = "David Fenwick and Adrian Ball and Peter Morgan", BookTitle = "Scanner Data and Price Indexes", Publisher = "University of Chicago Press", pages = "67-88", year = "2003", month = "January", URL = "http://www.nber.org/chapters/c9729", } @book{NBERfeen03-1, title = "Scanner Data and Price Indexes", author = "Robert C. Feenstra and Matthew D. Shapiro", institution = "National Bureau of Economic Research", type = "Book", publisher = "University of Chicago Press", year = "2003", URL = "http://www.nber.org/books/feen03-1", }