UK - James (Jim) Bamber. Has a weekly cartoon in Autosport, has been doing comcs for ages though prefers rallies to F1.

Brazil - Bruno Mantovani. Artist famed for his popular youtube videos. Pretty much everyone on f1 forums on the internet knows him.

France - Jean-Louis Fiszman. Another old-school artist, famed for particularly playing up a driver's faults, such as making Kimi an alcoholic whose car is powered by vodka.

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I'm kinda ignoring Cirebox for France as it seems he's Renault-contracted, hence the heavy Renault positive lean of his comics.