1. Dries Buytaert uses the phrase “a chain of many unexpected events” to describe Drupal in an interview with Noel Hidalgo, 26 July 2007, “episode 13-dries on drupal,” http://luckofseven.com/vlog/episode13 .
2. Tag1 Consulting, Inc., “Section 3: The Throttle Module,” http://books.tag1consulting.com/scalability/drupal/performance/throttle
3. Dries Buytaert, 26 July 2007, interview with Noel Hidalgo, “episode 13 — dries on drupal,” http://luckofseven.com/vlog/episode13 .
4. DigiDave, Drupal Nation: Software to Power the Left, http://blog.digidave.org/2008/12/drupal-nation-software-to-power-the-left
5. Groups.Drupal, Growth Charts, http://groups.drupal.org/node/1980