my $arrayref1 = [ 9, 10, 'a big fat hen' ];

my $arrayref2 = [
    $arrayref1,
    $arrayref1,
    $arrayref1,
];

print "Only showing super-structure:\n";
print Dumper $arrayref2;
print "Showing both sub-structure and super-structure:\n";
print Dumper $arrayref1, $arrayref2;