Open University Press, 29 Open University, 27 Oxford University Press, 25 OXFORD, 19 Ombak, 5 Obor Indonesia, 5 OCLC Online Computer Library Center, 4 OCLC,4 OJK, 2 O'Reilly Media,2 Obor Pustaka,2 Obor, 2 Open University of Hong Kong Press, 2 Offset Printer, 2 Ohio University Press, 1 OJK Institute,1 Orbis Books, 1 Orbis,1 Omsons Publications, 1 Organisasi perburuhan Internasional, 1