This image is the work of M. C. Escher, in 1961, as it's presented on WikiArt . Just like WikiArt, we claim that we can display a low-resolution version of this image under the US "fair use" exception, because it is being used as an illustration for educational purposes.
Appears on these pages
Bach wrote fifteen three-part inventions. In this three-part Dialogue, the Tortoise and Achilles...