Chemical tuning of the colossal magnetoresistance of ferromagnetic perovskites J. Fontcuberta, B. Martínez, A. Seffar, S. Piñol, J. L. García-Muñoz and X. Obradors Europhys. Lett., 34 5 (1996) 379-384 Published online: 01 September 2002 DOI: 10.1209/epl/i1996-00467-y