diff --git a/handyhelper/__init__.py b/handyhelper/__init__.py
index aa6ed39..14269ab 100644
--- a/handyhelper/__init__.py
+++ b/handyhelper/__init__.py
@@ -28,7 +28,7 @@ async def search(txt):
     ref = doc.find('div', {'id': 'citation'}).get_text()
     pdf = doc.find('embed', {'id': 'pdf'})['src']
 
-    pdf = pdf[:(pdf.find(".pdf"+4))]
+    pdf = pdf[:(pdf.find(".pdf")+4)]
     
     return {
         'ref': ref,