2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/123764The models in the two papers hep-ph/0608068 and hep-ph/0701254 by Chang et al. with the so-called shadow gauge and scalar fields are nothing but convenient tailored versions of our model in hep-th/0403039. The same remarks applies to the work in hep-th/0612165 by Meissner and Nicolai.4 pages, no figuresHigh Energy Physics - TheoryHigh Energy Physics - Phenomenologytext