Julio Ribera Trucó started his career in his native Spain, working together with Pedro Alférez for several Spanish magazines under pseudonyms like Jules McSide and Bop. Ribera cooperated on Florita, a magazine for young girls, in 1945, and created 'Rosy'. He began a collaboration with Yumbo in 1950, and created series like 'Pepin y Sulfato' and 'Platillos Volantes'.
