| Oafr | African studies | 
| Oafr Sanakirjat | African studies Dictionaries (reference only) | 
| Oe | Ethiopia | 
| Oq | Hamic languages | 
| Oä | Egyptology | 
| Ob | Assyriology | 
| Oc | Comparative Semitic linguistics | 
| Os | Syriac and Aramaic | 
| Ou | Ugarit | 
| Oel | Elamite | 
| Oat | Arabic texts | 
| Oav | Arabic varia: history, Islamic culture, literature and history | 
| Oag | Arabic grammar books, textbooks | 
| Oad | Arabic dictionaries (reference only) | 
| Ohv | Hebrew varia: Judaism, history of literature, etc | 
| Oi 1 | Iranian: Old and Central Iranian languages | 
| Oi 2 | Iranian: New Iranian languages | 
| Oi 3 | Iranian: Pre-Islamic time (history/culture) | 
| Oi 4 | Iranian: Islamic time (history/culture) | 
| Oi Sanakirjat | Iranian: Dictionaries and reference books (reference only) | 
| Ov | Varia | 
| Om 1 | Comparative Altaic studies | 
| Om 2 | Peoples of Siberia and Central Asia | 
| Om 3 | Mongolian | 
| Om 4 | Buryat | 
| Om 5 | Daguor | 
| Om 6 | Monguor | 
| Om 7 | Moghol | 
| Om 8 | Oirat | 
| Om 9 | Kalmyk | 
| Om 10 | Comparative Mongolian and other Mongolian languages | 
| Om 11 | Manchu | 
| Om 12 | Jurchen | 
| Om 13 | Goldi (Nanai) | 
| Om 14 | Olcha | 
| Om 15 | Oroch | 
| Om 16 | Orok | 
| Om 17 | Udege | 
| Om 18 | Tungusic (Evenki) | 
| Om 19 | Lamut (Even) | 
| Om 20 | Solon | 
| Om 21 | Negidal | 
| Om 22 | Samagir | 
| Om 23 | Comparative Tungusic and other Tungusic languages | 
| Om 24 | Turkish (Contemporary Turkish, Ottoman Turkish) | 
| Om 25 | Gagauz | 
| Om 26 | Azerbaijani | 
| Om 27 | Turkmen | 
| Om 28 | Karachay-Balkar | 
| Om 29 | Kumyk | 
| Om 30 | Bashkir | 
| Om 31 | Tatar (Volga Tatar) | 
| Om 32 | Nogai | 
| Om 33 | Kazakh and Karakalpak | 
| Om 34 | Kyrgyz | 
| Om 35 | Central Turkish languages | 
| Om 37 | Uzbek | 
| Om 38 | Modern Uyghur (Eastern Turki, Taranchi) | 
| Om 39 | Old Turkish | 
| Om 40 | Tuva, tofa | 
| Om 41 | Yakut | 
| Om 42 | Khakas | 
| Om 43 | Altai (Oirot) | 
| Om 44 | Bulgar (Volga and Danubian Bulgar) | 
| Om 45 | Chuvash | 
| Om 46 | Karaim | 
| Om 47 | Comparative Turkology and other Turkish languages | 
| Om 48 | North-eastern Siberians, Aleuts, Inuits, Yupiit, Ainu | 
| Om 53 | Tibetan, Tangut | 
| Om 54 | South-East Asia, Oceania and Australian | 
| Om 500 | Korean reference books (reference only) | 
| Om 501 | Korean dictionaries (reference only) | 
| Om 502 | Korean textbooks | 
| Om 503 | Korean philology | 
| Om 504 | Korean literature | 
| Om 505 | Korean literary research | 
| Om 506 | Korean history | 
| Om 507 | Korean cultural history and art | 
| Om 508 | Korean religion and philosophy | 
| Om 509 | Korean society | 
| Om 510 | Japanese reference books (reference only) | 
| Om 511 | Japanese dictionaries (reference only) | 
| Om 512 | Japanolese textbooks | 
| Om 513 | Japanese philology | 
| Om 514 | Japanese literature | 
| Om 515 | Japanese literary research | 
| Om 516 | Japanese history | 
| Om 517 | Japanese cultural history | 
| Om 518 | Japanese religion and philosophy | 
| Om 519 | Japanese society | 
| Om 520 | Chinese reference books (reference only) | 
| Om 521 | Chinese dictionaries (reference only) | 
| Om 522 | Chinese textbooks | 
| Om 523 | Chinese philology | 
| Om 525 | Chinese literary research | 
| Om 526 | Chinese history | 
| Om 527 | Chinese cultural history and art | 
| Om 528 | Chinese religion and philosophy | 
| Om 529 | Chinese society | 
| Om 55 | Asia, general | 
| O Isokokoiset | Varia: large books | 
| Oi  Isokokoiset | Iranian: large books | 
| Om Isokokoiset | East and Central Asia: large books | 
| Oä Isokokoiset | Egyptology: large books | 
| Oys Isokokoiset | South Asia: large books | 
| OYs 1 | Indian philology: reference books | 
| OYs 2 | Veda literature | 
| OYs 3 | Hindu literature | 
| OYs 4 | Buddhist literature | 
| OYs 5 | Jainism literature | 
| OYs 8 | Indian literary history | 
| OYs 9 | South Asian history, culture, religions and philosophy | 
| OYs 10 | Sanskrit linguistics | 
| OYs 11 | Middle Indo-Aryan languages | 
| OYs 12 | Bengali | 
| OYs 13 | Hindi and Urdu | 
| OYs 15 | Other Indo-Aryan languages | 
| OYs 16 | Dravidian languages | 
| OYs 17 | Munda languages, Andamanese languages, Burushaski | 
| OYs 19 | Comparative Indo-European linguistics | 
| OYs 20 | Hittite | 
| OYs 21 | Tocharian | 
| OYs Sanakirjat | South Asian studies Dictionaries (reference only) |