Specific Rules #3 for Conference Title (required) to Citing Conference Proceedings Vancouver Style: Conference titles containing a Greek letter, chemical formula, or another special character

Capitalize the first word of a title unless the title begins with a Greek letter, chemical formula, or another special character that might lose its meaning if capitalized.

2,2-dichloro-1,1,1-trifluoroethane.

von Willebrand disease and genetic testing.

If a title contains a Greek letter or some other symbol that cannot be reproduced with the type fonts available, substitute the name for the symbol. For example, Ω becomes omega.

Synthesis of β-amino acids.

or

Synthesis of beta-amino acids

If a title contains superscripts or subscripts that cannot be reproduced with the type fonts available, place the superscript or subscript in parentheses.

TiO2 nanoparticles.

or

TiO(2) nanoparticles.

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