Which preposition to use with saga

OF Occurrences 144%

CHARLES C. RAFN SAGA OF ERIC

in Occurrences 9%

The following ballad introduces the saga in prose.

to Occurrences 1%

A moment's recollection of what is now perhaps the most familiar of Teutonic saga to the ordinary reader, the text of Wagner's "Ring of the Nibelung," will give ample evidence of that mental attitude.

Which preposition to use with  saga