California Code, Probate Code - PROB § 248

When title to real or personal property, or any interest therein, vests, other than by laws of succession, on the heirs, heirs of the body, issue, or children of any person, without other description, or means of identification of the persons embraced in the description, any person interested in the property as the heir, heir of the body, issue, or child, or his or her successor in interest, or the personal representative of any interested person or of his or her successor in interest, may file a verified petition in the superior court of the county in which the property or any part thereof is situated, setting forth briefly the deraignment of title of petitioner, a description of the property affected, and so far as known to the petitioner, the names, ages, and residences of the heirs, heirs of the body, issue or children whose identity is sought to be determined, and if any is dead or if the residence of any is unknown, stating the facts, and requesting that a decree be entered determining and establishing the identity of the persons embraced in the general description.