Man pages matching name mdu in section 1:

mdu.1.pl	debian 10 / manpages-pl
mdu.1.en	debian 10 / mtools
mdu.1.de	debian 11 / manpages-de
mdu.1.pl	debian 11 / manpages-pl
mdu.1.en	debian 11 / mtools
mdu.1.de	debian 12 / manpages-de
mdu.1.pl	debian 12 / manpages-pl
mdu.1.en	debian 12 / mtools