Charles H. Bennett, John Gill. Relative to a Random Oracle A, P^A != NP^A != co-NP^A with Probability 1. SIAM Journal on Computing, 10(1):96-113, 1981.
@article{BennettG81, title = {Relative to a Random Oracle A, P^A != NP^A != co-NP^A with Probability 1}, author = {Charles H. Bennett and John Gill}, year = {1981}, researchr = {https://researchr.org/publication/BennettG81}, cites = {0}, citedby = {0}, journal = {SIAM Journal on Computing}, volume = {10}, number = {1}, pages = {96-113}, }