Samuel R. Buss. The Modal Logic of Pure Provability. Notre Dame Journal of Formal Logic, 31(2):225-231, 1990.
@article{Buss90:0, title = {The Modal Logic of Pure Provability}, author = {Samuel R. Buss}, year = {1990}, tags = {modal logic, logic}, researchr = {https://researchr.org/publication/Buss90%3A0}, cites = {0}, citedby = {0}, journal = {Notre Dame Journal of Formal Logic}, volume = {31}, number = {2}, pages = {225-231}, }