Joe Deninzon's "Power Chord Workout" in December 2012 issue of STRINGS Magazine
http://www.allthingsstrings.com/Technique/VIOLIN/Warm-Up-to-a-New-Style-with-a-Power-Chord-Workout
http://www.allthingsstrings.com/Technique/VIOLIN/Warm-Up-to-a-New-Style-with-a-Power-Chord-Workout
http://www.allthingsstrings.com/Technique/VIOLIN/Warm-Up-to-a-New-Style-with-a-Power-Chord-Workout