@article{1093635503, author = {Shannon, Gary P.}, title = {Provable forms of Martin's axiom.}, journal = {Notre Dame J. Formal Logic}, volume = {31}, number = {2}, year = {1990}, pages = { 382-388}, language = {en}, url = {http://dml.mathdoc.fr/item/1093635503} }
Shannon, Gary P. Provable forms of Martin's axiom.. Notre Dame J. Formal Logic, Tome 31 (1990) no. 2, pp. 382-388. http://gdmltest.u-ga.fr/item/1093635503/