diff --git a/docs/conf.py b/docs/conf.py
index c119cd0de8..06ead2b2a7 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -519,6 +519,8 @@ def setup(app):
     r'https://indico.desy.de/event/22731/.*',
     # https://indico.belle2.org/event/8470/contributions/55871/ is frequently generating 403 Client Error
     r'https://indico.belle2.org/event/8470/.*',
+    # https://doi.org/10.1142/S0217732321020016 is frequently generating 403 Client Error
+    r'https://doi\.org/10.1142/.*',
     # CERN doesn't maintain its SSL certs well enough to not have SSLErrors
     r'https://twiki.cern.ch/.*',
     # tags for a release won't exist until it is made, but the release notes