Stanley S. Wainer. Ordinal Recursion, and a Refinement of the Extended Grzegorczyk Hierarchy. Journal of Symbolic Logic, 37(2):281-292, 1972.
@article{Wainer72, title = {Ordinal Recursion, and a Refinement of the Extended Grzegorczyk Hierarchy}, author = {Stanley S. Wainer}, year = {1972}, tags = {refinement}, researchr = {https://researchr.org/publication/Wainer72}, cites = {0}, citedby = {0}, journal = {Journal of Symbolic Logic}, volume = {37}, number = {2}, pages = {281-292}, }