The author¸author attribute should give the full name of the author, in the order as it is conventionally spoken. In much of the Western world, the family name goes last.
If there are multiple authors, separate them by the word and,¸and rather than by commas. The reason for this is that BibTEX¸name parsing has special algorithms that use this convention to allow parsing of names in some foreign languages, as well as names with qualifiers, like Jr., and those algorithms could be adapted by other programs that process file headers. Even simple programs could separate the names by splitting at the word and.
Here is the author¸author attribute from this document's file header:
%%% author = "Nelson H. F. Beebe",
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