fix the docs build

Author: zingale

docs/source/conf.py

@@ -45,6 +45,9 @@
     'IPython.sphinxext.ipython_console_highlighting',
     'sphinx.ext.githubpages']
 
+# bibtex
+bibtex_bibfiles = ["refs.bib"]
+
 # Add any paths that contain templates here, relative to this directory.
 templates_path = ['_templates']