A Shortest 2-Basis for Boolean Algebra in Terms of the Sheffer Stroke.

Robert Veroff A Shortest 2-Basis for Boolean Algebra in Terms of the Sheffer Stroke. 1-9 2003 31 J. Autom. Reasoning 1 http://dx.doi.org/10.1023/A:1027322305654 db/journals/jar/jar31.html#Veroff03