| Artist | Titles | 1.
| Ostner, Charles Leopold, 1828-1913, painter. | 9 | 2.
| Ostrander, Philip, painter. (attributed to) | 1 | 3.
| Ostrowe, Karen, sculptor. | 1 | 4.
| Ostrowski, Stanislaw Kazimierz, 1879-1947, sculptor. | 0 | 5.
| See: Ostrowski, Stanislaw Kazimierz Waclaw, 1879-1947, sculptor. | 1 | 6.
| Ostrowski, Stanislaw Kazimierz Waclaw, 1879-1947, sculptor. | 1 | 7.
| Ostrowski, Stanislaw Kazmierz, 1879-1947, sculptor. | 0 | 8.
| See: Ostrowski, Stanislaw Kazimierz Waclaw, 1879-1947, sculptor. | 1 | 9.
| Ostrowski, Stanslaw K., 1879-1947, sculptor. | 0 | 10.
| See: Ostrowski, Stanislaw Kazimierz Waclaw, 1879-1947, sculptor. | 1 | 11.
| Ostrowsky, Stanislaw, 1879-1947, sculptor. | 0 | 12.
| See: Ostrowski, Stanislaw Kazimierz Waclaw, 1879-1947, sculptor. | 1 | 13.
| O'Sullivan, Danny, contractor. | 1 | 14.
| O'Sullivan, painter. | 1 |
|