California Code, Code of Civil Procedure - CCP § 751.20

Whenever judgment in an action authorized by this chapter has been entered as to any real property, no other action relative to all or any part of the same property shall be tried until proof has first been made to the court that all persons who appeared in the first action or their successors in interest have been personally served pursuant to this chapter either within or without the State more than one month before the time to plead expired.