When using a renowned poet's quote on a gravestone does one write the quote in italics and also use quotation marks around the quote?
Gravestones are rather like headlines - brevity is preferred. So a quote from a poet would likely be in the same font as any other text, and probably not attributed. After all, an epitaph is not a thesis dissertation, nor is it a newspaper column.
Put it another way - if a poet is quoted but neither identified as a quote nor properly attributed, who gets sued for plagiarism?