Quark sea structure functions of the nucleon in a statistical model L.A. Trevisan, C. Mirez, T. Frederico and L. Tomio Eur. Phys. J. C, 56 2 (2008) 221-229 Published online: 02 July 2008 DOI: 10.1140/epjc/s10052-008-0651-1