California Code, Probate Code - PROB § 12520

(a) If a nondomiciliary decedent's will has been admitted to probate in a sister state or foreign nation and satisfies the requirements of this article, probate of the will in an ancillary administration proceeding is governed by this article.

(b) If a nondomiciliary decedent's will has been admitted to probate in a sister state or foreign nation, but does not satisfy the requirements of this article, the will may be probated in an ancillary administration proceeding pursuant to Part 2 (commencing with Section 8000).