A method for preparing and verifying a document, comprising the steps of: presenting the document to a document-registering office in a machine-readable format; editing the document to add an identification code associated with a non-copiable object; signing the edited document using a private key of the document-registering office; printing the digitally signed document in a machine-readable form; presenting the document and the object to an inspecting authority; recovering the digitally signed document from the machine-readable form of the printed document; verifying the digital signature of the document-registering office; and verifying that the identification code in the document corresponds to that of the presented object.