diff --git a/modules/book/book.module b/modules/book/book.module
index 56f839a..644f2b6 100644
--- a/modules/book/book.module
+++ b/modules/book/book.module
@@ -251,11 +251,14 @@ function theme_book_title_link($link) {
  *
  * This list may be used for generating a list of all the books, or for building
  * the options for a form select.
+ *
+ * @param $reset
+ *   Reset the cache of stored books.
  */
-function book_get_books() {
+function book_get_books($reset = FALSE) {
   static $all_books;
 
-  if (!isset($all_books)) {
+  if (!isset($all_books) || $reset) {
     $all_books = array();
     $result = db_query("SELECT DISTINCT(bid) FROM {book}");
     $nids = array();