1999
National Gallery of Art, 1852
National Gallery of Art, 1974
National Gallery of Art, 1858
National Gallery of Art, 1544
National Gallery of Art, 1988
National Gallery of Art, 1973
National Gallery of Art, 1472
National Gallery of Art, 1933
National Gallery of Art, 1995
National Gallery of Art, 1895
National Gallery of Art, 1937
National Gallery of Art, 1901
![Pi [working proof 2]](https://api.nga.gov/iiif/cd9ef14b-ffc9-4b54-8bff-f34993de222f/full/843,/0/default.jpg)
![Untitled (Purple Mezzotint) [trial proof H]](https://api.nga.gov/iiif/2c4c23fa-98f0-40ef-929f-c94320d54961/full/843,/0/default.jpg)
