diff --git a/doc/source/conf.py b/doc/source/conf.py
index 040b790..9e49597 100644
--- a/doc/source/conf.py
+++ b/doc/source/conf.py
@@ -61,7 +61,7 @@ templates_path = ['_templates']
 source_suffix = '.rst'
 
 # The encoding of source files.
-source_encoding = 'utf-8-sig'
+source_encoding = 'utf-8'
 
 # The master toctree document.
 master_doc = 'contents'