diff --git a/docs/conf.py b/docs/conf.py
index 408a018..22d9d1d 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -277,4 +277,4 @@
 
 
 # Example configuration for intersphinx: refer to the Python standard library.
-intersphinx_mapping = {"http://docs.python.org/": None}
+intersphinx_mapping = {"python": ("https://docs.python.org/3", None)}
diff --git a/docs/index.rst b/docs/index.rst
index 6b9713d..69bb0a3 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -13,7 +13,7 @@ describe a Python implementation presently under
 development.
 
 .. _reference implementation:
-    http://www.po.gso.uri.edu/~codiga/utide/utide.htm
+    https://www.po.gso.uri.edu/~codiga/utide/utide.htm
 
 .. [codiga2011] Codiga, D.L., 2011. Unified Tidal Analysis and Prediction
     Using the UTide Matlab Functions. Technical Report 2011-01.