diff --git a/config/ratelimit.py b/config/ratelimit.py
index 4d59c8dcf3..435076c726 100644
--- a/config/ratelimit.py
+++ b/config/ratelimit.py
@@ -21,6 +21,7 @@ def validatecaptcha(request):
     return False
 
 
+# refer https://django-ratelimit.readthedocs.io/en/stable/rates.html for rate
 def ratelimit(
     request, group="", keys=[None], rate=settings.DJANGO_RATE_LIMIT, increment=True
 ):
diff --git a/config/settings/base.py b/config/settings/base.py
index 9f3db9e747..e5e1976226 100644
--- a/config/settings/base.py
+++ b/config/settings/base.py
@@ -324,6 +324,7 @@ def GETKEY(group, request):
     return "ratelimit"
 
 
+# https://django-ratelimit.readthedocs.io/en/stable/rates.html
 DJANGO_RATE_LIMIT = env("RATE_LIMIT", default="5/10m")
 
 GOOGLE_RECAPTCHA_SECRET_KEY = env("GOOGLE_RECAPTCHA_SECRET_KEY", default="")