To subscribe a Google Calendar indirectly shared through group/public

If a calendar is shared to individuals, it will be displayed in My/Other-calendars widgets (in left pane of calendar window) automatically.  However, this is not true when it is shared to public or groups (GoogleApps Contacts, GoogleGroups).

In settings of each calendar (from menu button at the end of each calendar), there is "calendar address" section showing 3 types of links: XML, ICAL, and HTML.  Note that intention of HTML link is to obtain the public URL to view a read-only version of the calendar without signing in to Google Calendar.  It is not to add the calendar into My/Other-calendars list.

Given that we are member of group to which the calendar is shared, here is how to add the calendar into our My/Other-calendars list.

1. Obtain the ICAL link from searching, calendar owner or existing member (e.g., via email or chat).
2. Follow "subscribe" procedure:  At the bottom of the calendar list on the left, click the Add down-arrow button and select Add by URL.  Then input the ICAL link.