2005
National Gallery of Art, 1977
National Gallery of Art, 1840
National Gallery of Art, 1817
National Gallery of Art, 1889
National Gallery of Art, 1930
National Gallery of Art, 1936
National Gallery of Art, 1884
National Gallery of Art, 1972
National Gallery of Art, 1847
National Gallery of Art, 1997
National Gallery of Art, 1935
National Gallery of Art, 1870
![Nilpferdkopf mit geöffnetem Maul (Hippo Mouth Open) [p. 27]](https://api.nga.gov/iiif/40890b8f-34f2-4042-a758-055cee939ead/full/843,/0/default.jpg)
![Untitled [trial proof of 4th state]](https://api.nga.gov/iiif/05b1c47b-2ab4-44ae-a8ee-92450c0b95c3/full/843,/0/default.jpg)
