[Thanks to Dymphie]
Beginning March 1, 2007, NLM will adjust the way it assigns title abbreviations to journals indexed for MEDLINE® and cited in PubMed®. Rather than independently assigning title abbreviations for each title, NLM will accept the abbreviations assigned by the International Standard Serial Number (ISSN) Centre and modify the punctuation and capitalization to conform to NLM standards. The ISSN key title abbreviation will be stripped of all punctuation except for parentheses around a title qualifier. The first letter of each word will be capitalized. Subfields will not be included in the abbreviation. The abbreviation used by GenBank (ISO Abbreviation) will follow the same punctuation and capitalization formatting as the NLM title abbreviations. Because NLM uses a single record approach in its cataloging, ISSN qualifiers for specific formats will be dropped.