Cal. Civil Code § 1899.2

(a) When a museum is required to give a lender notice pursuant to the provisions of this chapter, the museum shall be deemed to have given a lender notice if the museum mails the notice to the lender at the lender’s address and proof of receipt is received by the museum within 30 days from the date the notice was mailed. If the museum does not have an address for the lender, or if proof of receipt is not received by the museum, notice shall be deemed given if the museum publishes notice at least once a week for three successive weeks in a newspaper of general circulation in both the county in which the museum is located and the county of the lender’s address, if any. (b) In addition to any other information prescribed in this chapter, notices given pursuant to it shall contain the lender’s name, the lender’s address, if known, the date of the loan and, if the notice is being given by the museum, the name, address, and telephone number of the appropriate office or official to be contacted at the museum for information regarding the loan. (c) For the purposes of this section, a museum is “located” in the county of a branch of the museum to which a loan is made. In all other instances, a museum is located in the county in which it has its principal place of business.