The physical requirements which the documents making up the European patent application, i.e. request, description, claims, drawings and abstract, must satisfy are set out in Rule 49 and with regard to drawings in Rule 46. In particular, when amending the application documents, typed amendments should be the norm and any handwritten amendments must be clearly legible to a person who is not a technical specialist (for more details see A-III, 3.2). The President of the EPO may lay down further special formal or technical requirements for the filing of documents, in particular with regard to the filing of documents by technical means (Rule 2(1)). Notes on the preparation of OCR-readable patent applications were published in OJ EPO 1993, 59. In relation to the drawings, the particular requirements are dealt with in A-IX. The latter Chapter should, however, also be consulted with regard to the other documents mentioned, as the comments therein on the provisions of Rule 49 are of general application. Here, attention need only be drawn to Rule 49(7) which states that "the lines of each sheet of the description and of the claims shall preferably be numbered in sets of five, the numbers appearing on the left side, to the right of the margin".