Test that docs compile under latex as well --needed for PDF building
diff --git a/tox.ini b/tox.ini
index 56603da..39fe024 100644
--- a/tox.ini
+++ b/tox.ini
@@ -17,6 +17,7 @@
 basepython = python2.7
 commands =
     sphinx-build -W -b html -d {envtmpdir}/doctrees docs docs/_build/html
+    sphinx-build -W -b latex -d {envtmpdir}/doctrees docs docs/_build/latex
     sphinx-build -W -b doctest -d {envtmpdir}/doctrees docs docs/_build/html
     sphinx-build -W -b linkcheck docs docs/_build/html