Comment on the paper “Improving Poor Man’s Kramers-Kronig analysis and Kramers-Kronig constrained variational analysis” Auteur(s): Rousseau E., Izard N., Bantignies J.-L., Felbacq D. (Article) Publié: -Spectrochimica Acta Part A Molecular And Biomolecular Spectroscopy [1994-...], vol. 259 p.119849 (2021) Texte intégral en Openaccess : Ref HAL: hal-03228703_v1 DOI: 10.1016/j.saa.2021.119849 Exporter : BibTex | endNote Résumé: We clarify some analytical expressions existing in the literature, • Within the correct formulae we conclude that there is no need for an ad hoc improvement on the opposite to the title paper, • We highlight the symmetry properties of the function to be integrated in order to agree with the usual assumptions made to derive the Kramers-Kronig relations, • The analytical formula we provide may be used to increase the accuracy of the "Poor Man's Kramers-Kronig analysis" method and the "Kramers-Kronig constrained variational analysis" method.