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Patrias K, author; Wendling D, editor. Citing Medicine: The NLM Style Guide for Authors, Editors, and Publishers [Internet]. 2nd edition. Bethesda (MD): National Library of Medicine (US); 2007-.

Cover of Citing Medicine

Citing Medicine: The NLM Style Guide for Authors, Editors, and Publishers [Internet]. 2nd edition.

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2015 Foreword

NLM conceived this 2nd edition after the 2005 revision of ANSI/NISO Z39.29 Bibliographic References published by the National Information Standards Organization. Some of the changes in that revision addressed the then new and evolving content appearing on the Internet. Since that time, there have been numerous changes in publishing. Researchers often use electronic rather than print materials thanks to ready access, and determining the type of Web resource one is referencing has become difficult as differences between Web sites, online books, online databases, etc. are disappearing and all are searchable.

As we are making changes and adding more examples to Citing Medicine, we are also waiting to see if there will be changes in ANSI/NISO Z39.29. In 2010 the ANSI/NISO standard was renewed, as revisions to a sister international standard (ISO/FDIS 690 Information and documentation – Guidelines for bibliographic references and citations to information resources) was being voted on. Now ANSI/NISO Z39.29 is again due for review. The standard is in need of updating, and perhaps simplification. Some examples:

  • For materials on the Internet the medium designator [Internet] is required following the title, and the URL is required. In 2015, almost everyone recognizes a string starting with http: or https: or doi: as a URL or address for something on the Internet. Do we still need to require Internet in brackets as a medium designator?
  • Citations are slightly different between books on the Internet, databases on the Internet, and Web sites, and different in print and electronically depending on if a smaller section is a contribution to or just a part of the whole. As the Internet evolves, a lot of content today is created directly for the Internet, not reformatted from print materials. Materials that started out as books on the Internet have sometimes become more database-like than book-like, searched to find the relevant information rather than read as whole books or chapters. Does it still make sense to follow publisher information for a Web site or book or single database on the Internet with a semicolon, but to end the publisher information for serial databases and retrieval systems with a period?
  • Today Internet resources may not readily provide information on who is responsible for the content, and where that person or organization may be. For example, a site may provide an organization name, but have no indication of where that organization is geographically. Authors can spend hours searching for this information to include it in brackets, or choose the allowable [publisher unknown], [place unknown], etc. However, is it helpful to indicate the information not known?

Perhaps it is time to rethink the necessary information to identify a cited work today, and to better standardize citations across different media and publication types. Authorship, titles, and dates (content created or published, revised, and cited if on the Internet) are still crucial – but what else is essential? In addition, is it possible to apply the same order and punctuation to all references? Print materials are still used and need consideration; however, electronic resources prevail and citing these materials needs to be simplified.

NLM hopes for a future simplification of the national standard for bibliographic references.

/Joyce E.B. Backus /

Joyce Backus

Associate Director for Library Operations

National Library of Medicine


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