17.—(1) A document purporting to be a copy of a part or all of a development plan and to be certified by an officer of a planning authority as a correct copy shall be evidence of the plan or part, unless the contrary is shown, and it shall not be necessary to prove the signature of the officer or that he or she was in fact such an officer.

(2) Evidence of all or part of a development plan may be given by production of a copy thereof certified in accordance with this subsection and it shall not be necessary to produce the plan itself.