http://home.comcast.net/~alloy-artifacts/snapon-bluepoint-tools-p3.html
http://www.sundt.com/why-sundt/history/
http://www.greatbuildings.com/architects/William_Van_Alen.html
http://www.uwec.edu/geography/ivogeler/w367/materials/materials.htm
http://www.aviewoncities.com/nyc/empirestate.htm
http://www.aviewoncities.com/nyc/chrysler.htm
http://www.sundt.com/why-sundt/history/
http://www.greatbuildings.com/architects/William_Van_Alen.html
http://www.uwec.edu/geography/ivogeler/w367/materials/materials.htm
http://www.aviewoncities.com/nyc/empirestate.htm
http://www.aviewoncities.com/nyc/chrysler.htm