diff --git a/maths/average_median.py b/maths/average_median.py
index 0257e3f76..57e01368b 100644
--- a/maths/average_median.py
+++ b/maths/average_median.py
@@ -1,6 +1,10 @@
-def median(nums):
+from typing import Union
+
+
+def median(nums: Union[int, float]) -> Union[int, float]:
     """
     Find median of a list of numbers.
+    Wiki: https://en.wikipedia.org/wiki/Median
 
     >>> median([0])
     0