private function findEmailId($member_id)
 {
     $contacty_types = $this->findAllContactTypes();
     if (empty($contacty_types)) {
         return false;
     } else {
         $contact_type_id = array_search('EMAIL', $contacty_types);
         if (is_int($contact_type_id)) {
             $student = new Core_Model_Member_Student();
             $student->setMember_id($member_id);
             $info = $student->fetchContactInfo($contact_type_id);
             if ($info instanceof Core_Model_MemberContacts) {
                 return $info->getContact_details();
             }
         } else {
             return false;
         }
     }
 }