%0 Journal Article %A Nomura, Kazumasa %T Spin models of index 2 and Hadamard models %J Journal of Algebraic Combinatorics %D 2003 %P 5-17 %V 17 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/JAC_2003__17_1_a4/ %G en %F JAC_2003__17_1_a4