| #161 | Obzornik za matematiko in fiziko. -- Ljubljana : Društvo matematikov, fizikov in astronomov SR Slovenije, 1951-. -- ISSN 0473-7466 |
| #162 | Ocean & coastal management. -- Barking : Elsevier Applied Science, 1992-. -- ISSN 0964-5691 print. -- ISSN 1873-524X online |
| #163 | Optics and spectroscopy. -- Moscow : Nauka/Interperiodica, 1959-. -- ISSN 0030-400X print. -- ISSN 1562-6911 online |
| #164 | Opto-Electronics Review. -- Warszawa : Stowarzyszenie Elektryków Polskich, 1992-. -- ISSN 1230-3402 print. -- ISSN 1896-3757 online |
| #165 | Optoelectronics, instrumentation and data processing. -- New York : Allerton, 1984-. -- ISSN 8756-6990 print. -- ISSN 1934-7944 online |
| #166 | Organic geochemistry. -- Oxford : Pergamon Press, 1977-. -- ISSN 0146-6380 print. -- ISSN 1873-5290 online |
| #167 | Palaeoworld. -- Amsterdam : Elsevier Science, 2006-. -- ISSN 1871-174X print. -- ISSN 1875-5887 online |
| #168 | Perseus. -- Brno : B.R.N.O. -sekce pozorovatelů proměnných hvězd, 1991-. -- ISSN 1213-9300 |
| #169 | Physics of atomic nuclei. -- Moscow : Nauka Interperiodica, 1993-. -- ISSN 1063-7788 print. -- ISSN 1562-692X online |
| #170 | The physics of metals and metallography. -- New York : Pergamon Press, 1957-. -- ISSN 0031-918X |