Aggregates Manager - May 4, 2010
   Modular Valves Keep the Powder Flowing on Marble Hill

Biomass Magazine - February 2010 Issue
   Colmac Energy's Secret to Success: Reliability and Maximum Uptime

Powder and Bulk Engineering - July 1999 Issue
   "Rotary valves keep on turnin'"

Powder and Bulk Engineering
   "Rotary valve return on investment:
     Doing the math"