Box with pocket for extractable leaflet

A box formed from a single piece of punched and crease-lined cardboard or the like, defining an internal pocket for containing an extractable leaflet, comprising:

• at least four consecutive main panels,
• a flap which projects from the first main panel and is superposed on and glued to the last main panel in the finished box,
• an end panel which projects from the last main panel and has a width substantially equal to that of the first main panel, to which it faces in the box interior to form with said first panel a pocket for containing said leaflet,
• at least one panel for closing at least one end of the box,
• the main panels, the end panel and said flap being separated one from the other by parallel longitudinal folding lines, wherein from the penultimate main panel there projects a supplementary panel separated from it by a folding line transverse to said longitudinal folding lines, from said supplementary panel there projecting a tab separated from it by a likewise longitudinal folding line, the supplementary panel and the tab projecting from it being folded into the box interior about their folding lines such that the supplementary panel and respectively said tab are superposed on the penultimate main panel and respectively on that main panel adjacent to it on the side towards the first panel, the main panels and also the end panel being folded about their longitudinal folding lines such that the end panel is superposed on the first main panel in the box interior to form therewith said pocket, while the free longitudinal edge of the end panel rests on the free longitudinal edge of the tab of the supplementary panel, which supports this end panel to prevent it from flexing towards the interior of the box.