I only just came across this illustrator the other day. She's been working hard in the industry for many years and is happily still at it! Her work is available on Imagekind. Here are some especially nice book covers and a catalogue cover from the 1950s. I love her line work in these book cover illustrations, and the catalogue gives us a taste of her quintessentially mid-century style of character illustration. She also created some whimsical advertisements while working in Chicago, New York and Boston. See more here.
Cornelius van Velsen (Dutch 1921-1910) designed 170 posters as well as LP covers and illustrated children's books. During WW2, he forged identity cards for the resistance.