http://www.marketingteacher.com/Lessons/lesson_generic_strategies.htm
http://www.coursework4you.co.uk/essays-and-dissertations/porter-generic-strategies.php
More notes: http://university-essays.tripod.com/porters_generic_strategies.html
Presentation: http://tutor2u.net/business/presentations/strategy/genericstrategies/default.html