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The purpose of this comment is to present the perturbation approach proposedby Maiz J. Math. Phys. 60, 012103 (2019) in a clearer way. The results of ourstraightforward procedure agree with those obtained by that author except forone case in which we obtain the exact result while he obtained an approximateone. In addition to it, we show that for sufficiently deep double-wellpotentials the perturbation approach deteriorates considerably.

Comment on: "Development of the perturbation theory using polynomial solutions" J. Math. Phys. 60, 012103 (2019)