diff --git a/requirements.txt b/requirements.txt
old mode 100755
new mode 100644
index b34878c..0bc244f
--- a/requirements.txt
+++ b/requirements.txt
@@ -48,7 +48,7 @@ nbformat==4.3.0
 networkx==2.0
 ngram==3.3.0
 nltk==3.2.4
-notebook==4.4.1
+notebook==6.1.5
 numpy==1.13.1
 olefile==0.44
 openpyxl==2.4.5