| #51 | Acta crystallographica, Section A, Crystal physics, diffraction, theoretical and general crystallography. -- Copenhagen : Munksgaard, 1968-1982. -- ISSN 0567-7394 print. -- ISSN 1600-8596 online |
| #52 | Acta crystallographica, Section B, Structural crystallography and crystal chemistry. -- Copenhagen : Munksgaard, 1968-1982. -- ISSN 0567-7408 print. -- ISSN 1600-8650 online |
| #53 | Acta crystallographica, Section A, Foundations of crystallography. -- Oxford : Blackwell Publishing on behalf of the International Society of Crystallography, 1983-. -- ISSN 0108-7673 print. -- ISSN 1600-5724 online |
| #54 | Acta crystallographica, Section B, Structural science. -- Copenhagen : Munksgaard, Int. Booksellers and Publishers, 1983-. -- ISSN 0108-7681 print. -- ISSN 1600-5740 online |
| #55 | Acta crystallographica, Section C, Crystal structure communications. -- Copenhagen : Munksgaard, 1983-. -- ISSN 0108-2701 print. -- ISSN 1600-5759 online |
| #56 | Acta cytobiologica et morphologica. -- Sofia : Bulgarian Academy of Sciences, 1989-1993. -- ISSN 0861-0509 |
| #57 | Acta Endocrinologica, New series. -- Bucureşti : Editura Academiei Române, 2005-. -- ISSN 1841-0987 print. -- ISSN 1843-066X online |
| #58 | Acta entomologica bohemoslovaca. -- Praha : Academia, 1965-1992. -- ISSN 0001-5601 |
| #59 | Acta Environmentalica Universitatis Comenianae. -- Bratislava : Univerzita Komenského, 1993-. -- ISSN 1335-0285 |
| #60 | Acta ethnographica Academiae Scientiarum Hungaricae. -- Budapest : Akadémiai Kiadó, 1950-1990. -- ISSN 0001-5628 |