Emery vs. Hubbard model for cuprate superconductors: a composite operator method studyAdolfo Avella, Ferdinando Mancini, Francesco Paolo Mancini and Evgeny PlekhanovEur. Phys. J. B, 86 6 (2013) 265DOI: https://doi.org/10.1140/epjb/e2013-40115-3