People who have actually paid Dennis to work for them . . . 

(Many, more than once) 

NBC Television ... ESPN Radio  ...  KOVR-TV Sacramento ...  KOIN-TV Portland OR ...  WAGT-TV Augusta GA ...  WOWK-TV Huntington WV ...  KVIA-TV El Paso TX ...  KTWO Radio- Casper WY ...  The Peter Communications (Consultants) ...  The Donahue Show - Multimedia Productions NY ...  Pogen Crunch Cream Cookies ... Louisiana Downs Racetrack ... Daiwu Laganza ... Blue Cross and Blue Shield of Wyoming ... Matrix Direct Insurance Services ... Mitsubishi ...   Pacific Mutual ...  San Diego Union-Tribune ...   Orange County Register ...  PennySaver ... Intel Microprocessors ... Caterpillar Tractor ... Washington Mutual ... Toshiba Telecommunications Systems ... Solar Turbines International ... Beckman Instruments ...  Fisher Electronics ...  Sanyo ...  Romex Wiring ...  Kawasaki Motors Corporation ... TraveLodge ... The San Diego Padres Baseball Club. 
(Partial list)