Alan Cobham. Some Remarks Concerning Theories with Recursively Enumerable Complements. Journal of Symbolic Logic, 28(1):72-74, 1963.
@article{Cobham63, title = {Some Remarks Concerning Theories with Recursively Enumerable Complements}, author = {Alan Cobham}, year = {1963}, researchr = {https://researchr.org/publication/Cobham63}, cites = {0}, citedby = {0}, journal = {Journal of Symbolic Logic}, volume = {28}, number = {1}, pages = {72-74}, }