diff --git a/docs/conf.py b/docs/conf.py
index 5371015..d211470 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -12,4 +12,4 @@
 html_last_updated_fmt = '%d-%b-%y %H:%M'
 
 def setup(app):
-    app.add_stylesheet("css/ribbon.css")
+    app.add_css_file("css/ribbon.css")
diff --git a/docs/requirements-docs.txt b/docs/requirements-docs.txt
index b3188dd..74a3b7a 100644
--- a/docs/requirements-docs.txt
+++ b/docs/requirements-docs.txt
@@ -1,15 +1 @@
-tox
-Sphinx
-doc8
-docutils
-setuptools
-six
-sphinx_rtd_theme>=0.4.3
-sphinxcontrib-blockdiag
-sphinxcontrib-needs>=0.2.3
-sphinxcontrib-nwdiag
-sphinxcontrib-seqdiag
-sphinxcontrib-swaggerdoc
-sphinxcontrib-plantuml
-sphinx_bootstrap_theme
 lfdocs-conf
diff --git a/docs/tox.ini b/docs/tox.ini
index edac8c3..811bb5e 100644
--- a/docs/tox.ini
+++ b/docs/tox.ini
@@ -1,11 +1,14 @@
 [tox]
 minversion = 1.6
-envlist = docs,
+envlist = docs
 skipsdist = true
 
 [testenv:docs]
 basepython = python3
-deps = -r{toxinidir}/requirements-docs.txt
+deps =
+    -r{toxinidir}/requirements-docs.txt
+    -chttps://git.onap.org/doc/plain/etc/upper-constraints.os.txt
+    -chttps://git.onap.org/doc/plain/etc/upper-constraints.onap.txt
 commands =
     sphinx-build -b html -n -d {envtmpdir}/doctrees ./ {toxinidir}/_build/html
     echo "Generated docs available in {toxinidir}/_build/html"
@@ -16,7 +19,10 @@
 
 [testenv:docs-linkcheck]
 basepython = python3
-#deps = -r{toxinidir}/requirements-docs.txt
+deps =
+    -r{toxinidir}/requirements-docs.txt
+    -chttps://git.onap.org/doc/plain/etc/upper-constraints.os.txt
+    -chttps://git.onap.org/doc/plain/etc/upper-constraints.onap.txt
 commands = echo "Link Checking not enforced"
 #commands = sphinx-build -b linkcheck -d {envtmpdir}/doctrees ./ {toxinidir}/_build/linkcheck
 whitelist_externals = echo