@article{1183739308, author = {Steel, John}, title = {Descending Sequences of Degrees}, journal = {J. Symbolic Logic}, volume = {40}, number = {1}, year = {1975}, pages = { 59-61}, language = {en}, url = {http://dml.mathdoc.fr/item/1183739308} }
Steel, John. Descending Sequences of Degrees. J. Symbolic Logic, Tome 40 (1975) no. 1, pp. 59-61. http://gdmltest.u-ga.fr/item/1183739308/