diff --git a/Lib/Search/BookSearch.php b/Lib/Search/BookSearch.php
index 105a2bb..e327543 100644
--- a/Lib/Search/BookSearch.php
+++ b/Lib/Search/BookSearch.php
@@ -59,6 +59,11 @@ class BookSearch
         $this->queryParts[] = $queryText;
     }
 
+    public function addRange($field, $min = '*', $max = '*')
+    {
+        $this->queryParts[] = sprintf('%s:[%s TO %s]', $field, $min, $max);
+    }
+
     public function addSortField($field, $order = \SolrQuery::ORDER_DESC)
     {
         $this->query->addSortField($field, $order);
diff --git a/NetBiblio.php b/NetBiblio.php
index 62cb3dd..4616bc7 100644
--- a/NetBiblio.php
+++ b/NetBiblio.php
@@ -580,18 +580,29 @@ class NetBiblio extends WebService
      * ° queryText : the text to search for
      * ° queryType : the field to search in, defaults to 'text'
      *
-     * ° genre : array of 'genreCode' to search for
      * ° jeunesse : only display books for kids (must have format 'jeunesse' => array('filtrer' => 'filtrer')
+     *
      * ° producerCode : filter by 'producerCode'
+     * ° genreCode : filter by 'genreCode'
+     * ° author : filter by 'author'
      * ° reader : filter by 'reader'
+     * ° motsMatieres : filter by 'motsMatieres'
+     *
+     * ° duration : exact duration in hours, duration are saved as float in Solr
+     * ° durationMin : minimal duration in hours
+     * ° durationMax : maximal duration in hours
      *
      * ° count : number of results we want
      * ° page : page to start at (0 is the first)
      *
+     * Shortcuts :
+     *
+     * ° producer : synonym for 'producerCode' (see above)
+     * ° genre : synonym for 'genreCode' (see above)
+     *
      * Deprecated, but still in use on mobile apps :
      *
      * ° category : synonym for 'genre' (see above)
-     * ° producer : synonym for 'producerCode' (see above)
      *
      * Return value :
      *
@@ -658,6 +669,14 @@ class NetBiblio extends WebService
             $bs->addQuery(1, 'jeunesse');
         }
 
+        if(isset($queryArray['duration'])) {
+            $bs->addQuery($queryArray['duration'], 'duration');
+        } else if(isset($queryArray['durationMin']) || isset($queryArray['durationMax'])) {
+            $min = isset($queryArray['durationMin']) ? $queryArray['durationMin'] : '*';
+            $max = isset($queryArray['durationMax']) ? $queryArray['durationMax'] : '*';
+            $bs->addRange('duration', $min, $max);
+        }
+
         $availableFields = array('producerCode', 'genreCode', 'author', 'reader', 'motsMatieres');
         foreach($availableFields as $q) {
             if(isset($queryArray[$q]) && (