Article 17 of Law of Evidence

Merchants' books shall not constitute evidence against non-merchants. Nevertheless, the entries recorded therein concerning what merchants have supplied may constitute a basis permitting the judge to direct a supplementary oath to either party, even in matters that may not be proved by testimonial evidence. Mandatory commercial books—whether regularly or irregularly kept—shall constitute evidence against their merchant owner in respect of what his opposing litigant, whether a merchant or a non-merchant, relies upon, provided that entries in the interest of the owner of the books shall also be considered evidence in his favour.