diff --git a/requirements_for_documentation.txt b/requirements_for_documentation.txt
index 871b4dcaf2d89725b0a137f56751003738220520..97d60932f84175e5061db8788c91366f1ad7a1cb 100644
--- a/requirements_for_documentation.txt
+++ b/requirements_for_documentation.txt
@@ -1,19 +1,19 @@
-< alabaster==0.7.12
-< commonmark==0.9.1
-< docutils==0.16
-< Jinja2==2.11.2
-< Markdown==3.2.2
-< MarkupSafe==1.1.1
-< pockets==0.9.1
-< recommonmark==0.6.0
-< sphinx-markdown-tables==0.0.15
-< sphinxcontrib-applehelp==1.0.2
-< sphinxcontrib-devhelp==1.0.2
-< sphinxcontrib-htmlhelp==1.0.3
-< sphinxcontrib-jsmath==1.0.1
-< sphinxcontrib-napoleon==0.7
-< sphinxcontrib-qthelp==1.0.3
-< sphinxcontrib-restbuilder==0.2
-< sphinxcontrib-serializinghtml==1.1.4
-< sphinxcontrib-sqlalchemyviz==0.5
-< sphinxcontrib-websupport==1.2.2
+alabaster==0.7.12
+commonmark==0.9.1
+docutils==0.16
+Jinja2==2.11.2
+Markdown==3.2.2
+MarkupSafe==1.1.1
+pockets==0.9.1
+recommonmark==0.6.0
+sphinx-markdown-tables==0.0.15
+sphinxcontrib-applehelp==1.0.2
+hinxcontrib-devhelp==1.0.2
+sphinxcontrib-htmlhelp==1.0.3
+sphinxcontrib-jsmath==1.0.1
+sphinxcontrib-napoleon==0.7
+sphinxcontrib-qthelp==1.0.3
+sphinxcontrib-restbuilder==0.2
+sphinxcontrib-serializinghtml==1.1.4
+sphinxcontrib-sqlalchemyviz==0.5
+sphinxcontrib-websupport==1.2.2