%0 Journal Article %A Korec, Ivan %T Definability of arithmetical operations from binary quadratic forms %J Communications in Mathematics %D 1998 %P 135-144 %V 6 %N 1 %U http://geodesic.mathdoc.fr/item/COMIM_1998_6_1_a15/ %G en %F COMIM_1998_6_1_a15