Search for: Title Author Subject Series that begins with: 10 20 30 50 100 per page < Previous 10 Headings Next 10 Headings > Browse Headings # Operational Research Society of New Zealand. 1 Operational Research Society of Singapore. 1 Operations Research Society of America 9 SEE ALSO later heading: Institute for Operations Research and the Management Sciences 10 Operations Research Society (U.S.) -- SEE: Operations Research Society of America 9 Operator Films 1 Operators (Musical group : Canada) 2 Opernhaus Zürich 1 Opeth (Musical group) 7 Ophthalmic Genetics Study Club 1 Ophthalmological Society of New Zealand 2 10 20 30 50 100 per page < Previous 10 Headings Next 10 Headings >