protected function findByExternalID()
    {
        $sModelClass = $this->getModelClass();
        if ($this->bWithTrashed) {
            $this->obModel = $sModelClass::withTrashed()->getByExternalID($this->sExternalID)->first();
        } else {
            $this->obModel = $sModelClass::getByExternalID($this->sExternalID)->first();
        }
    }