Simplify the following text for a Grade 12 native English-speaking person.
Original: According to Richard Earle , author of The Art of Cause Marketing , the Smokey Bear campaign is recognized as among the most powerful and enduring of all public service advertising .
Simplified: According to Richard Earle , author of The Art of Cause Marketing , the Smokey Bear campaign is recognized one of the most powerful and lasting of all public service advertising .