### re-worked version of your original code

my $ref1 = [(0..9)];      ### start with anon array refs
my $ref2 = [('a'..'l')];  ### from the very beginning

my ($aOne, $aTwo) = &f($ref1, $ref2);
print '@a1 is:  '. "@{$aOne}\n";
print '@a2 is:  '. "@{$aTwo}\n";

sub f {
    my $a1 = shift || die 'Hey! I expected an array ref ';
    my $a2 = shift || die 'expected array ref here too ';

    ### do something, for example ...
    @{$a2} = reverse @{$a2};

    return ($a1, $a2);
}

__END__
@a1 is:  0 1 2 3 4 5 6 7 8 9
@a2 is:  l k j i h g f e d c b a