Starting with N° 50 The illustration size for the covers is back to a simple pocket format, the design is brand new.
Before N° 50 the format is "à l'italienne" (Larger than high) with an inner flap, so cover illustrations are larger and more detailled.
Before episode n°24 , there was no flap part to the cover. Illustrations were pocket book sized "à la française" (Higher than large), from N° 1 to N°23.