| #551 | Audio engineering. -- UNITED STATES : Orange, Ct. : Radio Magazines, Inc., c1947-c1954., 1947-1954. -- ISSN 0275-3804 |
| #552 | Audio stereoplay. -- Haar bei München : WEKA Media Publishing, 2023-. -- ISSN 0171-4147 |
| #553 | Audiotecnica : Il problema del rumore. -- ITALY : Torino: Centro Acustico Nazionale, Ufficio Stampa e Pubblicazioni., 1953-. -- ISSN 0004-7619 |
| #554 | AudioXpress. -- Peterborough : Audio Amateur, 2001-. -- ISSN 1548-6028 |
| #555 | Aufbau. -- GERMANY : Berlin: Aufbau-Verlag., 1945-1958. -- ISSN 0863-0348 |
| #556 | Augenoptiker. -- GERMANY : Leinfelden-Echterdingen: Konradin-Verl. Kohlhammer., 1946- |
| #557 | Aula : Revue pro vysokoškolskou a vědní politiku. -- Praha : Centrum pro studium vysokého školství, 1993-2015. -- ISSN 1210-6658 |
| #558 | AusIMM bulletin and proceedings. -- AUSTRALIA : Parkville, Vic: Australasian Institute of Mining and Metallurgy., 1986-1989. -- ISSN 0818-3848 |
| #559 | The AusIMM proceedings. -- Parkville : Australasian Institute of Mining and Metallurgy, 1990-. -- ISSN 1034-6783 |
| #560 | Aussenhandel der Tschechischen Republik. -- Praha : PP Agency, 1993. -- ISSN 1210-5562 |