Deleting Google Calendar events owned by someone else

It's sometimes needed to delete calendar events owned by someone else, for example if they've left the organisation.

1. Using the sidebar, search for their email address to view their calendar
2. Find the event (the version in their calendar, not yours)
3. Delete it

If it's already been deleted from their calendar, but not from everyone else's (which can happen if the event has been transferred a few times).

1. Edit the event in your calendar (or someone else's)
2. Where the selector would be to change the calendar the event is in is a long c_xxxx@group.calendar.google.com calendar name.
3. Take this name, and enter it in the sidebar to view its calendar
4. Find the event in this calendar
5. Delete it