Deconfinement phase transition in a two-dimensional model of interacting 2 × 2 plaquettesA. Fledderjohann, A. Klümper and K.-H. MütterEur. Phys. J. B, 72 4 (2009) 559-565DOI: https://doi.org/10.1140/epjb/e2009-00389-6