Héctor Germán Oesterheld created two popular characters for the Misterix magazine, of the Abril publisher: Bull Rocket and Sergeant Kirk.

It was arranged that Bull Rocket would stay in Misterix, written by new authors, and Oesterheld would take Kirk to his new publishing house, alongside the artist Hugo Pratt.

[1] Some comics included in the anthologies soon become successful enough to have their own runs, such as Ernie Pike and Ticonderoga by Pratt, Randall the Killer by Arturo del Castillo, Sherlock Time by Alberto Breccia, Joe Zonda and Rolo, el marciano adoptivo by Francisco Solano López.

The weekly publication El Eternauta, by Oesterheld and Solano López, was first published on September 4, 1957, at "Hora Cero semanal", and lasted until 1959.

Frontera fell into bankruptcy in 1959, and the magazines were taken by the publisher Emilio Ramírez to pay debts.