Charles Rackoff. On the Complexity of the Theories of Weak Direct Powers. Journal of Symbolic Logic, 41(3):561-573, 1976.
@article{Rackoff76, title = {On the Complexity of the Theories of Weak Direct Powers}, author = {Charles Rackoff}, year = {1976}, researchr = {https://researchr.org/publication/Rackoff76}, cites = {0}, citedby = {0}, journal = {Journal of Symbolic Logic}, volume = {41}, number = {3}, pages = {561-573}, }