According to "New Hart's Rules", "house style will dictate" whether to use the serial comma. "The general rule is that one style or the other should be used consistently." No association with region or dialect is suggested, other than that its use has been strongly advocated by Oxford University Press. Its use is preferred by Fowler's "Modern English Usage". It is recommended by the United States Government Printing Office, Harvard University Press, and the classic "Elements of Style" of Strunk and White.