\input zb-basic
\input zb-ioport
\iteman{io-port 50166331}
\itemau{Henle, James M.; Zwicker, William S.}
\itemti{Ultrafilters on spaces of partitions}
\itemso{J. Symb. Log. 47, No. 1, 137-146 (1982).}
\itemcc{}
\itemut{}
\itemli{}
\end