@code{nil}), diary entries are included also (in weekly and monthly
calendars only). If the variable @code{cal-tex-rules} is non-@code{nil}
(the default is @code{nil}), the calendar displays ruled pages
-in styles that have sufficient room.
+in styles that have sufficient room. You can use the variable
+@code{cal-tex-preamble-extra} to insert extra LaTeX commands in the
+preamble of the generated document if you need to.
@node Holidays
@section Holidays