89. The following must be expressly alleged and supported by affidavit:(1) the contestation of a signature or of a material part of any private writing, or of the fulfilment of the formalities required for the validity of a writing;
(2) the pretension of the heirs or legal representatives of the signatory of a document contemplated in paragraph 1, that they do not know the handwriting or signature of the person whom they represent;
(3) the contestation of a semi-authentic act;
(4) the contestation of a technology-based document on the ground of a violation of integrity ; in such a case the affidavit must state precisely the facts and reasons suggesting a probable violation of the document’s integrity.Failing such affidavit, the writings are held to be admitted or the formalities to have been fulfilled, as the case may be.