Help Requested: Who said this famous CPU quote?

Hello,

I need to know who said "CPU clock speeds will double approximately every 18 months." This is often sited in various forms as Sombody’s Law of Computers. I am trying to find out who the "Law" is credited to and what the exact wording is. If you can help me please email me at Jerbear246@aol.com or post a response.
Thank you!