2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/90195In quant-ph/0205017 v1 Chen, Wu and Yang formulated a necessary separability criterion based on a realignment method for matrices. This note is to point out that this criterion is identical to the necessary cross norm criterion previously put forward by this author.1 page, REVTeXQuantum Physicstext