context: One of the most significant contributors of Garm was Tove Jansson who started her career in the magazine as a cartoonist in 1929 when she was just fifteen.
source: Over time the former became the magazine's chief illustrator.
reference_original: Con el tiempo, la primera se convirtió en la ilustradora principal de la revista.
reference_flipped: Con el tiempo, el primero se convirtió en el ilustrador principal de la revista.