/**
* Returns whether a given ISBN (10 or 13) is valid. True indicates validity.
- * @param isbn string ISBN passed for check
+ * @param $isbn string ISBN passed for check
* @return bool
*/
public static function isValidISBN( $isbn ) {
* Determine where to get the list of book sources from,
* format and output them
*
+ * @throws MWException
* @return string
*/
private function showList() {