If you want to add this calendar to your google calendar, the public calendar is google ID: 7o28i7rv7oeagn5ha3huh2q12g@group.calendar.google.com

The URL (for add calendar by URL) is: https://calendar.google.com/calendar/embed?src=7o28i7rv7oeagn5ha3huh2q12g%40group.calendar.google.com

The Public ICal id is: https://calendar.google.com/calendar/ical/7o28i7rv7oeagn5ha3huh2q12g%40group.calendar.google.com/public/basic.ics