References 1. Lenskold Group, "2009 Lenskold Group/MarketSphere Marketing ROI and Measurements Study" (Manasquan, New Jersey: Lenskold Group, 2009). 2. D.L. Hoffman and T.P. Novak, "Social Media Strategy," in "Handbook on Marketing Strategy," ed. V. Shankar and G.S. Carpenter (Northampton, Massachusetts: Edward Elgar Publishing, in press). 3. T.P. Novak and D.L.