Opencart Getting Customers' telephone no

Question

I don't know how to get an array of Customers' telephone numbers in Opencart 2.0.2.0

I have found how to get email of customers' by looking at contact.php in the controller folder :

$results = $this - > model_sale_customer - > getCustomers($customer_data);

foreach($results as $result) {
  $emails[] = $result['email'];
}

Which one of these implementations will work? If neither then please help me.

1st.

$results = $this - > model_sale_customer - > getCustomers($customer_data);

foreach($results as $result) {
  $contact[] = $result['telephone'];
}

2nd

$results = $this - > model_sale_customer - > getCustomers($customer_data);

foreach($results as $result) {
  $contact[] = $result['contact'];
}