Le Van Bao, Ho Thuan. Key ad superkey for a closure function. Acta Cybern., 9(1):73-88, 1989.
@article{BaoT89, title = {Key ad superkey for a closure function}, author = {Le Van Bao and Ho Thuan}, year = {1989}, researchr = {https://researchr.org/publication/BaoT89}, cites = {0}, citedby = {0}, journal = {Acta Cybern.}, volume = {9}, number = {1}, pages = {73-88}, }