@article{1093888120,
author = {McLaughlin, Thomas G.},
title = {Degrees of unsolvability and strong forms of $\Lambda\_R+\Lambda\_R\not\subseteq \Lambda\_R$.},
journal = {Notre Dame J. Formal Logic},
volume = {18},
number = {1},
year = {1977},
pages = { 545-566},
language = {en},
url = {http://dml.mathdoc.fr/item/1093888120}
}
McLaughlin, Thomas G. Degrees of unsolvability and strong forms of $\Lambda_R+\Lambda_R\not\subseteq \Lambda_R$.. Notre Dame J. Formal Logic, Tome 18 (1977) no. 1, pp. 545-566. http://gdmltest.u-ga.fr/item/1093888120/