The Stepmother from Cincerella was animated by Frank Thomas, but Milt Kahl made some drawings like this to help develop the character design. I hope everyone realizes the incredible skill it takes to draw like that.
Junyi Wu - Character Design Page
Academy of Art Character and Creature Design Notes: Brittney Lee
Plomo: Special Edition, Trevor Spencer & Andrea Fernandez
Living Lines Library: Atlantis - The Lost Empire - Characters: Model Sheets Production Drawings