Similarities between the t-J and Hubbard models in weakly correlated regimes M.-B. Lepetit, M.-L. Doublet and Ph. Maurel Eur. Phys. J. B, 28 1 (2002) 49-54 Published online: 09 July 2002 DOI: 10.1140/epjb/e2002-00198-5