Jun Tarui. Smallest formulas for the parity of 2:::k::: variables are essentially unique. Theoretical Computer Science, 411(26-28):2623-2627, 2010. [doi]
@article{Tarui10, title = {Smallest formulas for the parity of 2:::k::: variables are essentially unique}, author = {Jun Tarui}, year = {2010}, doi = {10.1016/j.tcs.2010.03.022}, url = {http://dx.doi.org/10.1016/j.tcs.2010.03.022}, researchr = {https://researchr.org/publication/Tarui10}, cites = {0}, citedby = {0}, journal = {Theoretical Computer Science}, volume = {411}, number = {26-28}, pages = {2623-2627}, }