@article{1183743561, author = {Ahmad, Seema}, title = {Embedding the Diamond in the $\Sigma\_2$ Enumeration Degree}, journal = {J. Symbolic Logic}, volume = {56}, number = {1}, year = {1991}, pages = { 195-212}, language = {en}, url = {http://dml.mathdoc.fr/item/1183743561} }
Ahmad, Seema. Embedding the Diamond in the $\Sigma_2$ Enumeration Degree. J. Symbolic Logic, Tome 56 (1991) no. 1, pp. 195-212. http://gdmltest.u-ga.fr/item/1183743561/