add example

source/guides/access-calendar-feeds.rst

@@ -22,6 +22,21 @@ Find the different types of calendars
 
     -   The list of resources is configurable by your institution (TODO link to resources guide)
 
+.. admonition:: Example
+
+    The MPI for Human Development uses a two-step process for booking 
+    appointments of shared resources: 
+
+    1. A *resource committee* allocates time slots fairly across upcoming 
+       studies (in a dedicated room booking system outside of Castellum). 
+    2. Study recruiters are allowed to assign appointments within these time 
+       slots (in Castellum).
+
+    In order to check availability of a resource it is sufficient to subscribe 
+    to the "Per Resource" feed. However, to check whether it is possible to swap 
+    open slots with other studies users have to match this information with the 
+    external calendar.
+
 Reset user tokens
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