Friedberg, Richard M. Two recursively enumerable sets of incomparable degrees of unsolvabllity (solution of Post’s problem, 1944). (English) Zbl 0080.24302 Proc. Natl. Acad. Sci. USA 43, 236-239 (1957). Page: −5 −4 −3 −2 −1 ±0 +1 +2 +3 +4 +5 Show Scanned Page Cited in 1 ReviewCited in 83 Documents Keywords:Foundations; Philosophy; Mathematical Logic × Cite Format Result Cite Review PDF Full Text: DOI