Comment on: Quantitative study of the $f$ occupation in CeMIn5 and other cerium compounds with hard X-rays, [arXiv:1601.03270]

This comment clarifies the mixed definition of the cerium valence in the article entitled: Quantitative study of the $f$ occupation in CeMIn5 and other cerium compounds with hard X-rays, published in Journal of Electron Spectroscopy and Related Phenomena http://www.sciencedirect.com/science/article/pii/S0368204816300123 and available on arXiv:1601.03270. Indeed, it is unclear wether electrons belonging on hybridized f-states are part or not of the valence. When one tries to simulate the system, an Anderson impurity model only includes valence bands electrons and localized 4-f states. Therefore hybridized 4-f states are mixed with the localized ones. From a heavy fermion perspective it however essential to differentiate hybridized and localized states as only the second are responsible for strong correlations, such as obtained by susceptibility or direct comparisons to model systems.