Specific Rules #3 for Place of Publication (required) for Entire Journal Titles Vancouver Style: No place of publication can be found

If no place can be found but one can be reasonably inferred, such as Chicago as the place of publication for a journal of the American Medical Association, put the place name in square brackets.

ACOG Technology Assessment in Obstetrics and Gynecology. [Washington]: American College of Obstetricians and Gynecologists. No. 1, 2002 - .

If no place of publication can be found or inferred, use [place unknown].

Acta Radiologica: Therapy, Physics, Biology. [place unknown]: Societies of Medical Radiology in Denmark, Finland, Norway, and Sweden. Vol. 1, 1963 - Vol. 16, 1977.

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Citing Medicine: The NLM Style Guide for Authors, Editors, and Publishers [Internet]. 2nd edition. Chapter 1: Journals

Related:

General Rules for Place of Publication (required) for Entire Journal Titles Vancouver Style

Specific Rules #1 for Place of Publication (required) for Entire Journal Titles Vancouver Style: Non-US cities

Specific Rules #2 for Place of Publication (required) for Entire Journal Titles Vancouver Style: Multiple places of publication

Specific Rules #3 for Place of Publication (required) for Entire Journal Titles Vancouver Style: No place of publication can be found

Examples for Place of Publication (required) for Entire Journal Titles Vancouver Style