diff --git a/pyproject.toml b/pyproject.toml
index 68975f3..ccca7b6 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -41,7 +41,7 @@ dependencies = [
   "colorama",
   "curies >= 0.6.6",
   "networkx >= 2.8",
-  "openpyxl >= 3.0.9",
+  "openpyxl >= 3.1.5",
   "pillow >= 9.1.0",
   "pydantic < 2.0.0",
   "pyLODE < 3.0.0",
diff --git a/src/voc4cat/cli.py b/src/voc4cat/cli.py
index 8e90265..0a57ae4 100644
--- a/src/voc4cat/cli.py
+++ b/src/voc4cat/cli.py
@@ -386,7 +386,7 @@ def add_docs_subparser(subparsers, options):
     parser.add_argument(
         "--style",
         help="Select style of html documentation. (default: pylode)",
-        choices=("pylode"),
+        choices=("pylode",),
         default="pylode",
         type=str,
         required=False,