
Samuel Colman (American, 1832-1920)

Ruger Donoho (American, 1858-1916)

Rudolf Wacker (Austrian, 1893-1939)

Rudolf von Alt (Austrian, 1812-1905)

Rudolf von Alt (Austrian, 1812-1905)

Rudolf Ribarz (Austrian, 1848-1904)

Rudolf Ribarz (Austrian, 1848-1904)

Rudolf Ribarz (Austrian, 1848-1904)

Rudolf Ribarz (Austrian, 1848-1904)

Rudolf Ribarz (Austrian, 1848-1904)

Rudolf Ribarz (Austrian, 1848-1904)

Rudolf Ribarz (Austrian, 1848-1904)

Rudolf Ribarz (Austrian, 1848-1904)

Rudolf Ribarz (Austrian, 1848-1904)

Rudolf Ribarz (Austrian, 1848-1904)

Rudolf Quittner (Austrian, 1872–1910)

Rudolf Quittner (Austrian, 1872–1910)

Rudolf Junk (Austrian, 1880-1943)

Robert Swain Gifford (American, 1840 – 1905)

Robert S. Duncanson (American, 1821-1872)

Robert S. Duncanson (American, 1821-1872)

Robert Russ (Austrian, 1847–1922)

Robert Russ (Austrian, 1847–1922)

Robert Russ (Austrian, 1847–1922)

Robert Russ (Austrian, 1847–1922)

Robert Russ (Austrian, 1847–1922)

Robert Havell Jr. (American, 1793-1878)

Robert Frederick Blum (American, 1857-1903)

Robert Frederick Blum (American, 1857-1903)

Robert Frederick Blum (American, 1857-1903)