diff -r 945b144d68c1 -r cfc090f440d0 src/p4l/utils.py
--- a/src/p4l/utils.py	Wed Sep 04 15:18:22 2013 +0200
+++ b/src/p4l/utils.py	Wed Sep 04 16:17:04 2013 +0200
@@ -77,14 +77,14 @@
     else:
         query = query_without_acronym
     res_dict = {}
+    if not uri_list:
+        return res_dict
     # We build the filter string
     filter_str = ""
     for i,uri in enumerate(uri_list):
         res_dict[uri] = ""
-        if i==0:
-            filter_str = "?uri = <" + uri + ">"
-        else:
-            filter_str += " || ?uri = <" + uri + ">"
+        filter_str += (" || ?uri = <" + uri + ">") if i else ("?uri = <" + uri + ">") 
+
     # We request the labels
     res = requests.get(
         settings.SPARQL_QUERY_ENDPOINT,