If you want to insert this calendar into your personal Google calendar, use this link:
https://www.google.com/calendar/feeds/0j6s66tou4er4un5arbqv27o9c%40group.calendar.google.com/public/basic
If you want to use this calendar in a iCal Mac calendar, use this link:
https://www.google.com/calendar/ical/0j6s66tou4er4un5arbqv27o9c%40group.calendar.google.com/public/basic.ics