 The first story, "Le Tank", is the very first 12 board "test" story Franquin drew to convince Jijé of his abilities, which was later printed in "Spirou almanache 1947" of 1946.The following story, "La maison préfabriquée", is the episode Jijé famously had begun in "Spirou" issue #422, but handed over to Franquin, to continue five boards into the work from issue #427.Although this album is not regarded as part of the official series and was never republished, its four stories are all printed and available in the "hors-série" albums, HS1 "L'héritage" and HS2 "Radar le robot".