70(4)In any claim or action under this section, a certificate purporting to be signed by the Chairperson, Vice-Chairperson or secretary of the New Brunswick Farm Products Commission, or by the chairman or secretary of the New Brunswick Forest Products Commission, as the case may be, setting out the amount of an assessment is, without proof of the appointment, authority or signature of the person purporting to have signed the certificate, admissible in evidence and is, in the absence of evidence to the contrary, proof of the amount of the assessment set out in the certificate.