[http://books.google.com/books?id=rPFpyrUuaUsC&pg=PA121&lpg=PA121&dq=Comcast+Purchased+Amcell&source=bl&ots=BO-UwPIdC7&sig=-b4fcPuLk5unQk59N7CTPMaM-n4&hl=en&sa=X&ei=8pgCT8eAMaGdiAK2nLWxDg&ved=0CFkQ6AEwBg#v=onepage&q=Comcast%20Purchased%20Amcell&f=false Into the Value Zone:Gaining and Sustaining Competitive Advantage]</ref> | [http://books.google.com/books?id=rPFpyrUuaUsC&pg=PA121&lpg=PA121&dq=Comcast+Purchased+Amcell&source=bl&ots=BO-UwPIdC7&sig=-b4fcPuLk5unQk59N7CTPMaM-n4&hl=en&sa=X&ei=8pgCT8eAMaGdiAK2nLWxDg&ved=0CFkQ6AEwBg#v=onepage&q=Comcast%20Purchased%20Amcell&f=false Into the Value Zone:Gaining and Sustaining Competitive Advantage]</ref> |