 Blumenthal.CODEN assigned until 1998 and their disintegration can be found at the "International CODEN Directory" (ISSN 0364-3670), which has been published since 1980 as a microfiches issue.Finding a current CODEN is now best done with the online database of CASSI ("Chemical Abstracts Service Source Index"), covering all registered titles, CODEN, ISSN, ISBN, abbreviations for publications indexed by CAS since 1907, including serial and non-serial scientific and technical publications.