As far as I know, one needs to use double or single quotes for fonts if they contain spaces, like:
font-family: \"Times New Roman\", Times;
font-family: \'T
You can always put a specific font family name in quotes, double or single, so Arial, "Arial", and 'Arial' are equivalent. Only the CSS-defined generic font family names like sans-serif must be written without quotes.
Contrary to popular belief, a font name consisting of space-separated names such as Times New Roman need not be quoted. However, the spec recommends “to quote font family names that contain white space, digits, or punctuation characters other than hyphens”