www.time.com/time/classroom/unchained.pdfs/teacher.pdf
www.si.umich.edu/chico/UMS/Drummers/materials.html
http://xroads.virginia.edu/~hyper/wpa/wpahome.html
http://vi.uh.edu/pages/mintz/primary.htm
http://csmweb2.emcweb.com/durable/1997/10/29/feat/feat.1.html