[Bug-tar] GNU tar man page

[R.G.]

Hi !

Recently i have had to extract a multivolume tar file. It was my first
time doing such things and of course i opened tar man page. The
possibility of sending data for tar through standard input (via < and
>) was not mentioned there (i think it should be).

But more important is that there was no description of how to point
multiple files as an argument (e.g. for extracting a multivolume
archive).

Could you please insert some multivolume examples in man page?