California Code, Penal Code - PEN § 969

In charging the fact of a previous conviction of felony, or of an attempt to commit an offense which, if perpetrated, would have been a felony, or of theft, it is sufficient to state, “That the defendant, before the commission of the offense charged herein, was in (giving the title of the court in which the conviction was had) convicted of a felony (or attempt, etc., or of theft).”  If more than one previous conviction is charged, the date of the judgment upon each conviction may be stated, and all known previous convictions, whether in this State or elsewhere, must be charged.