Hewey, Dewey, Louie learn integrals

[Giancarlo Bassi]

Hi everyone!

I'm looking for the comics including Huey, Dewey, Louie
while are learning an integral (calculus in mathematics)
written at the blackboard.

I know only the author is Carl Barks.

I heard about that from an I.N.D.U.C.K.S. activist,
but I don't know how to search that item.

Thanks for any suggestion,

 	GB


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