code: func (r Dns_Domain_Registration) DeleteRegisteredNameserver(nameserver *string) (resp bool, err error) {
  	params := []interface{}{
  		nameserver,
  	}
  	err = r.Session.DoRequest("SoftLayer_Dns_Domain_Registration", "deleteRegisteredNameserver", params, &r.Options, &resp)
  	return
  }
docs: // The deleteRegisteredNameserver method deletes a nameserver that was registered, provided it is not currently serving a domain