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By doing a slight change to a beautiful and widely unknown argument by E. L.Stark [E. L. Stark, Application of a Mean Value Theorem for Integrals to SeriesSummation, Amer. Math. Monthly 85 (1978) 481--483.] we get a candidate to beconsidered as one of the shortest and most elementary proofs of the celebratedBasel Problem. Furthermore, we give a comprehensive list of references on thistopic, displayed in chronological order from Euler to present.

A One-Sentence and Truly Elementary Proof of the Basel Problem