Specific Rules #6 for Publisher (required) to Citing Entire Reports Vancouver Style: No publisher can be found

If no publisher can be found, use [publisher unknown].

Rome: [publisher unknown]; 1971.

Según:

Citing Medicine: The NLM Style Guide for Authors, Editors, and Publishers [Internet]. 2nd edition. Chapter 4: Scientific and Technical Reports

Related:

General Rules for Publisher (required) to Citing Entire Reports Vancouver Style

Specific Rules #1: Abbreviated words in publisher names

Specific Rules #2: Non-English publishers

Specific Rules #3: Government agencies and other national and international bodies as publisher

Specific Rules #4: Joint publication

Specific Rules #5: Multiple publishers

Specific Rules #6: No publisher can be found

Examples for Publisher (required) to Citing Entire Reports Vancouver Style