diff --git a/readthedocs-pip-requirements.txt b/readthedocs-pip-requirements.txt
index 5ec672a..8bfee76 100644
--- a/readthedocs-pip-requirements.txt
+++ b/readthedocs-pip-requirements.txt
@@ -1,2 +1,3 @@
 sphinx>=1.8.5
-sphinxcontrib-napoleon>=0.7
\ No newline at end of file
+sphinxcontrib-napoleon>=0.7
+beautifulsoup4>=4.7.1
\ No newline at end of file