sub process {
   my ( $ref ) = @_;

   for my $row ( @$ref ) {
      for my $elem( @$row ) {
         print "'$elem' ";
      }
      print "\n";
   }
}

my @data = ( [ qw( a b c d e) ],
             [ qw( L M N ) ],
             [ qw( 3 1 4 1 5 9 2 6 ) ],
            );

process \@data;