This document contains links to various websites about the Pittsburgh Steelers defensive line from the 1970s known as the "Steel Curtain" including Joe Greene, L.C. Greenwood, Dwight White, and Ernie Holmes. Links are provided to pages on Steelers.com, Facebook, Wikipedia, CBS News, Steelerstribute.com, ESPN.com and Steelerstoday.com that provide information about these players and the dominant Steelers defense of that era.