Organisation for Economic Co-operation and Development 47,531
Ovid, 43 B.C.-17 A.D. or 18 A.D 5,553
Offenbach, Jacques, 1819-1880 3,927
Ormandy, Eugene, 1899-1985 3,464
Oecd 3,046
Oxford University Press 2,989
Ōta, Tōshirō 2,287
Obama, Barack 2,180
Oak Ridge National Laboratory 2,152
Orthodox Eastern Church 1,965
Omar Khayyam 1,626
Organisation de coopération et de développement économiques 1,602
O'Neill, Eugene, 1888-1953 1,458
Obichere Collection 1,431
Orchestre de la Suisse romande 1,353
Ohio 1,314
O'Keeffe, John, 1747-1833 1,244
Organisation for European Economic Co-operation 1,186
Osler, William, Sir, 1849-1919 1,152
OECD Nuclear Energy Agency 1,138
Optical Society of America 1,120
Open University 1,101
Österreichische Nationalbibliothek 1,065
Oxford Academic eCollections 1,054
Organisation for Economic Co-operation and Development Development Centre 1,046
Orff, Carl, 1895-1982 1,041
Owen, John, 1616-1683 1,041
Oistrakh, David, 1908-1974 1,037
Olmerṭ, Ehud 959
Otway, Thomas, 1652-1685 954
Organization of American States 920
Opus Arte (Firm) 909
Oliphant, Mrs (Margaret), 1828-1897 888
Origen 864
Ozawa, Seiji, 1935- 857
Orchestre national de France 828
Orchestre de Paris 826
Orville H. Bullitt Classics Fund 814
Owen, Robert, 1771-1858 805
Ockeghem, Johannes, approximately 1410-1497 795
O.W. Ketcham Terra Cotta Works 794
Optic, Oliver, 1822-1897 746
Opéra-Comique (Paris, France) 745
Ozawa, Seiji, 1935-2024 744
Orwell, George, 1903-1950 741
Oregon 728
Oppenheim, E. Phillips (Edward Phillips), 1866-1946 723
Orchestre des concerts Lamoureux 712
Opéra de Paris 708
Otter, Anne Sofie von 708
Ouyang, Xiu, 1007-1072 704
Oates, Joyce Carol, 1938- 684
Obrist, Hans Ulrich 684
Organization of American States General Secretariat 679
O.R.S.T.O.M. (Agency : France) 633
Ostrovsky, Aleksandr Nikolaevich, 1823-1886 626
Office for Official Publications of the European Communities 624
Ortega y Gasset, José, 1883-1955 608
Ogilby, John, 1600-1676 589
Oz, Amos, 1939-2018 580
Osborn, Henry Fairfield, 1857-1935 575
Ortelius, Abraham, 1527-1598 554
Ormonde, James Butler, Duke of, 1610-1688 551
Oxenford, John, 1812-1877 547
Ohio State University 545
Oregon Department of Geology and Mineral Industries 534
Ontario 529
Ovid, 43 B.C.-17 or 18 A.D 529
Obrecht, Jacob, -1505 522
Österreichische Akademie der Wissenschaften 521
Ouida, 1839-1908 520
Orion Pictures 516
Ostermeyer, Robert 514
Office of the United Nations High Commissioner for Refugees 513
Österreichischer Rundfunk 510
Ostwald, Wilhelm, 1853-1932 509
Ohio Division of Geological Survey 503
Onslow, Georges, 1784-1853 500
Olivier, Laurence, 1907-1989 492
Orchestre de chambre de Lausanne 492
Österreichisches Statistisches Zentralamt 488
Olson, Charles, 1910-1970 484
Orchestra of the Age of Enlightenment 475
Oren, Mosheh (Surveyor) 469
Orchestre symphonique de Montréal 463
Orchestre national de l'O.R.T.F 461
Organisation for Economic Co-operation and Development Staff 461
Oklahoma Geological Survey 451
Oldmixon, Mr (John), 1673-1742 448
Olive Films 447
Office for the Arts at Harvard & Radcliffe 439
Overbrook Press 438
Öffentliche Kunstsammlung Basel 438
Österreichisches Museum für Angewandte Kunst 433
Olmsted, Frederick Law, 1822-1903 431
Opéra de Paris Orchestre 427
Owen, Robert Dale, 1801-1877 413
OECD 410
O'Hara, John, 1905-1970 405
Ortiz, Diego, approximately 1525-approximately 1570 405