@inbook{NBERc12369, Crossref = "NBERlern11-1", title = "Innovation Process and Policy: What Do We Learn from New Growth Theory", author = "Philippe Aghion", BookTitle = "The Rate and Direction of Inventive Activity Revisited", Publisher = "University of Chicago Press", pages = "515-520", year = "2011", month = "April", URL = "http://www.nber.org/chapters/c12369", } @book{NBERlern11-1, title = "The Rate and Direction of Inventive Activity Revisited", author = "Josh Lerner and Scott Stern", institution = "National Bureau of Economic Research", type = "Book", publisher = "University of Chicago Press", year = "2012", URL = "http://www.nber.org/books/lern11-1", }