@article{10_4064_fm_65_2_193_195, author = {R. Chandler}, title = {A generalized contradiction principle}, journal = {Fundamenta Mathematicae}, pages = {193--195}, publisher = {mathdoc}, volume = {65}, number = {2}, year = {1969}, doi = {10.4064/fm-65-2-193-195}, language = {en}, url = {http://geodesic.mathdoc.fr/articles/10.4064/fm-65-2-193-195/} }