public function getFieldInUse($groupField, $type = 'all', array $options = []) {
		$defaults = [
			'group' => $groupField,
			'order' => [$this->getDisplayField() => 'ASC'],
		];
		if ($type === 'list') {
			$defaults['fields'] = ['' . $this->getPrimaryKey(), '' . $this->getDisplayField()];
		}
		$options += $defaults;
		return $this->find($type, $options);
	}