Mickey's Mellerdrammer : Mickey Mouse and Minnie Mouse Original Animation Drawing (Walt Disney, 1933).
"I wish I was in Dixie! Hooray! Hooray!" Capturing one of the theatrical traditions of the time, Mickey and Minnie take on the roles of Topsy and Little Eva in this original animation drawing from Mickey's Mellerdrammer. This Wilfred Jackson-directed short debuted on March 18, 1933, and was loosely based on the well-known anti-slavery novel Uncle Tom's Cabin with the characters performing in a "Tom's Show" in a reflection of the cultural norms of the time. Performing a tap-dance together this image of Mickey and Minnie can be spotted near the 2:13 timestamp of the film when viewed online. Rendered in graphite to full-figures on the 12 field 2-peghole animation sheet numbered 121 in the bottom right.
It is very rare to have both characters in the same drawing!
The paper used by Disney studios in the 1920s-1930s contains a distinctive watermark, visible in one of the photos, which further attests to its authenticity.