Cal. Civil Code - CIV § 1146. Section 1146.A gift is a transfer of personal property, made voluntarily, and without consideration.
Cal. Civil Code - CIV § 1147. Section 1147.A verbal gift is not valid, unless the means of obtaining possession and control of the thing are given, nor, if it is capable of delivery, unless there is an actual or symbolical delivery of the thing to the donee.
Cal. Civil Code - CIV § 1148. Section 1148.A gift, other than a gift in view of impending death, cannot be revoked by the giver.