--- a/tox.ini	Tue Mar 07 13:13:23 2017 +0100
+++ b/tox.ini	Wed Mar 22 15:43:20 2017 +0100
@@ -26,9 +26,11 @@
 commands = /bin/sh -c "flake8 `xargs -a {toxinidir}/flake8-ok-files.txt`"
 
 [testenv:doc]
+skip_install = true
 changedir = doc
 deps =
   sphinx
+  -r{toxinidir}/requirements/doc.txt
 commands =
   {envpython} -c 'import sphinx; sphinx.main()' -b html -d {envtmpdir}/doctrees .  {envtmpdir}/html