Since 1995, It was decided to follow as much as possible the format A+ whose diffusion does not cease developing in Europe (currently well known as the A4). This decision answers a preoccupation with a standardization, while being essential a framework in which freedom can bloom.

This format was developed by Leonardo da Vinci who established that if the ratio of the large side of a rectangle and the small side is equal to the square root of 2, the division of the lenght in 2 equal parts, keeping this same relationship between the sides of the half surface. And reversely, the doubling of the surface around the large side maintains these same proportions.

In the pages of the site, the format of works presented will be indicated by this graphic of reference in which a red framework will express the relative size of work, follow-up of the explicit format, with the letter P for Portrait (vertical orientation as the french style)   or with the letter L for Landscape (or horizontal orientation as the italian style) and the measurements height x width in millimetre, such as for example :