@article{COMIM_1998__6_1_a15, author = {Korec, Ivan}, title = {Definability of arithmetical operations from binary quadratic forms}, journal = {Communications in Mathematics}, pages = {135--144}, publisher = {mathdoc}, volume = {06}, number = {1}, year = {1998}, mrnumber = {1822523}, zbl = {1024.03011}, language = {en}, url = {http://geodesic.mathdoc.fr/item/COMIM_1998__6_1_a15/} }