stored in the standard @code{ustar} header. While optional for
expanding sparse version 1.0 members, use of extended headers is
mandatory when expanding sparse members in older sparse formats: v.0.0
-and v.0.1 (The sparse formats are described in detail in @pxref{Sparse
-Formats}). So, for this format, the question is: how to obtain
+and v.0.1 (The sparse formats are described in detail in @ref{Sparse
+Formats}.) So, for this format, the question is: how to obtain
extended headers from the archive?
If you use a @command{tar} implementation that does not support PAX