You can try this data structure, it implements a directional map in a OO style:

Referals.pm
package Referals;

use Data::Dumper;

use strict;

sub new {
    shift;
    my $self = {};
    $self->{NAME} = shift;
    $self->{REFERALS} = [];
    bless $self;
    return $self;
}

sub add_referal {
    my $self = shift;
    push @{$self->{REFERALS}}, shift;
}

sub display {
    my $self = shift;
    print "Name: $self->{NAME}\nReferals:\n";
    print Dumper $self->{REFERALS};
}

1;

Referals.pl:
use Referals;

my $Bob = new Referals("Bob");
my $Joe = new Referals("Joe");
my $Jack = new Referals("Jack");
my $Henry = new Referals("Henry");
my $Gabe = new Referals("Gabe");
my $Pete = new Referals("Pete");
my $Tim = new Referals("Tim");

$Jack->add_referal($Bob);
$Bob->add_referal($Joe);
$Joe->add_referal($Henry);
$Jack->add_referal($Gabe);
$Gabe->add_referal($Pete);
$Gabe->add_referal($Tim);

$Jack->display;
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