Which rhyme scheme is used in this excerpt from “ballad of birmingham” by dudley randall?

“mother dear, may i go downtowninstead of out to play, and march the streets of birminghamin a freedom march today? ”“no, baby, no, you may not go, for the dogs are fierce and wild, and clubs and hoses, guns and jailsaren’t good for a little child.”“but, mother, i won’t be alone. other children will go with me, and march the streets of birminghamto make our country free.
“mother dear, may i go downtown

instead of out to play,

and march the streets of birmingham

in a freedom march today? ”

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