As a rule, it is a letter that attests to the proper execution by the notary in the presence of a deed, contract or other letter, or that verifies a fact or thing of which the notary has specific knowledge. Notarial certificates shall be accompanied by a visa on or annexed to an existing document and shall attest to its proper execution, authenticity and validity or its status and effects. As a security measure, the certificate may also contain information such as the number of pages, a description of the document, its title, and other distinctive elements, in order to prevent pages from being added or removed. If affixed, short certificates may also be marked with half sealed on the certificate and half on the rest. .