CAL. CCP. CODE § 96 : California Code - Section 96

(a) Any party may serve on any other party a request in substantially the following form:

TO: ____________________________________________ ,

attorney for ____________________________________:

You are requested to serve on the undersigned, within 20 days, a statement of: the names and addresses of witnesses (OTHER THAN A PARTY WHO IS AN INDIVIDUAL) you intend to call at trial; a description of physical evidence you intend to offer; and a description and copies of documentary evidence you intend to offer or, if the documents are not available to you, a description of them. Witnesses and evidence that will be used only for impeachment need not be included. YOU WILL NOT BE PERMITTED TO CALL ANY WITNESS, OR INTRODUCE ANY EVIDENCE, NOT INCLUDED IN THE STATEMENT SERVED IN RESPONSE TO THIS REQUEST, EXCEPT AS OTHERWISE PROVIDED BY LAW.

(b) The request shall be served no more than 45 days or less than 30 days prior to the date first set for trial, unless otherwise ordered.

(c) A statement responding to the request shall be served within 20 days from the service of the request.

(d) No additional, amended or late statement is permitted except by written stipulation or unless ordered for good cause on noticed motion.

(e) No request or statement served under this section shall be filed, unless otherwise ordered.

(f) The clerk shall furnish forms for requests under this rule.

(g) The time for performing acts required under this section shall be computed as provided by law, including Section 1013.