Book: "Guesstimation: Solving the World's Problems on the Back of a Cocktail Napkin" - April 21 2008 by Lawrence Weinstein (Author) and John A. Adam (Author) Book: Guesstimation 2.0: Solving Today's Problems on the Back of a Napkin Paperback – September 30 2012 by Lawrence Weinstein (Author), Patricia Edwards (Illustrator) Source: Columbia University The Nobel-prize-winning physicist, Enrico Fermi