\input zb-basic
\input zb-ioport
\iteman{io-port 50022975}
\itemau{Gragg, Karen M.; Kung, Joseph P. S.}
\itemti{Consistent dually semimodular lattices}
\itemso{J. Comb. Theory, Ser. A 60, No. 2, 246-263 (1992).}
\itemcc{}
\itemut{}
\itemli{}
\end