@book {Karch2007, title = {Democratic laboratories : policy diffusion among the American states}, year = {2007}, publisher = {University of Michigan Press}, organization = {University of Michigan Press}, address = {Ann Arbor}, keywords = {Diffusion of innovations {\textendash} United States., Political planning {\textendash} United States.}, isbn = {047209968X}, author = {Karch, Andrew} }