| Artist | Nationality | Dates |
|---|---|---|
| Indistinctly Signed, | American | 20th century |
| Indistinctly signed, Spanish | Spanish | 19th century |
| Indistinctly Signed, American, | American | 19th century |
| Indistinctly signed, Dutch, | Dutch | 20th century |
| Insley, Albert | American | 1842-1937 |