| #531 | Poľovníctvo a rybárstvo. -- Bratislava : Obzor, 1949-. -- ISSN 0231-8768 |
| #532 | Powder diffraction : an international journal of materials characterization. -- Newtown Square : International Centre for Diffraction Data, 1986-. -- ISSN 0885-7156 print. -- ISSN 1945-7413 online |
| #533 | Powder technology. -- Lausanne : Elsevier, 1967-. -- ISSN 0032-5910 print. -- ISSN 1873-328X online |
| #534 | Der Praktische Tierarzt : Zeitschrift für fortschrittliche Veterinärmedizin. -- Hannover : Schlütersche Verlagsanstalt, 1951-. -- ISSN 0032-681X |
| #535 | Praxis der Naturwissenschaften, Physik. -- Köln : Aulis-Verl. Deubner, 1973-2000. -- ISSN 0177-8374 |
| #536 | Precambrian research. -- Amsterdam : Elsevier, 1974-. -- ISSN 0301-9268 print. -- ISSN 1872-7433 online |
| #537 | Precision engineering. -- Guildford : IPC Science and Technology Press, 1979-. -- ISSN 0141-6359 print. -- ISSN 1873-2372 online |
| #538 | Prilozi. -- Bitola : Društvo za nauka i umetnost. -- ISSN 0420-0950 |
| #539 | Prilozi - Makedonska akademija na naukite i umetnostite, Matematičko-technički nauki. -- Skopje : Makedonska akad. na naukite i umetnostite, 1980-. -- ISSN 0351-3246 |
| #540 | The Princeton University Library chronicle. -- Princeton : Friends of the Princeton University Library, 1939-. -- ISSN 0032-8456 |