Oscar H. Ibarra, Nicholas Q. Trân. A Note on Simple Programs with Two Variables. Theoretical Computer Science, 112(2):391-397, 1993.
@article{IbarraT93, title = {A Note on Simple Programs with Two Variables}, author = {Oscar H. Ibarra and Nicholas Q. Trân}, year = {1993}, researchr = {https://researchr.org/publication/IbarraT93}, cites = {0}, citedby = {0}, journal = {Theoretical Computer Science}, volume = {112}, number = {2}, pages = {391-397}, }