I guess that would depend on what type of poetry you most prefer, but to tell you quite bluntly, the first name that comes to my mind when posed this question is Shel Silverstein.
Don't get me wrong. I love the works of Poe, Shakespear, ee cummings, Emily Dickinson, Langston Hughes, and so forth. But I would honestly hate to be the sort of person who'd claim to have outgrown "A Light in the Attic" or "Where the Sidewalk Ends."
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