Specific Rules #6 for Date of Publication (required) to Citing Conference Proceedings Vancouver Style: No date of publication or copyright can be found

If neither a date of publication nor a date of copyright can be found, but a date can be estimated because of material contained in the book itself or on accompanying material, place a question mark after the estimated date and place date information in square brackets.

6th Congress on Equine Medicine and Surgery; 1999 Dec 12-14; Geneva, Switzerland. Chene-Bourg (Switzerland): Editions Medecine et Hygiene; [1999?]. 181 p. English, French, German.

If neither a date of publication nor a date of copyright can be found nor can the date be estimated, use [date unknown].

Proceedings of the 1993 Medical Defense Bioscience Review; 1993 May 10-13; Baltimore, MD. Frederick (MD): US Army Medical Research and Development Command; [date unknown]. 3 vols.

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Citing Medicine: The NLM Style Guide for Authors, Editors, and Publishers [Internet]. 2nd edition. Chapter 3: Conference Publications

Related:

General Rules for Date of Publication (required) to Citing Conference Proceedings Vancouver Style

Specific Rules #1 for Date of Publication (required) to Citing Conference Proceedings Vancouver Style: Multiple years of publication

Specific Rules #2 for Date of Publication (required) to Citing Conference Proceedings Vancouver Style: Non-English names for months

Specific Rules #3 for Date of Publication (required) to Citing Conference Proceedings Vancouver Style: Seasons instead of months

Specific Rules #4 for Date of Publication (required) to Citing Conference Proceedings Vancouver Style: Date of publication and date of copyright

Specific Rules #5 for Date of Publication (required) to Citing Conference Proceedings Vancouver Style: No date of publication, but a date of copyright

Specific Rules #6 for Date of Publication (required) to Citing Conference Proceedings Vancouver Style: No date of publication or copyright can be found

Specific Rules #7 for Date of Publication (required) to Citing Conference Proceedings Vancouver Style: Options for date of publication

Example Entries for Date of Publication (required) to Citing Conference Proceedings Vancouver Style