Which preposition to use with courants

of Occurrences 14%

He was essentially French, or rather Parisian, knew everybody, and was au courant of all that went on politically and socially, and had a certain blague, that eminently French quality which is very difficult to explain.

with Occurrences 3%

During her absence, Mr. Murray wrote to her two or three times a week, and kept her au courant with the news of the day.

about Occurrences 1%

James Franklin published something in the New England Courant about the lawmakers of Massachusetts.

Which preposition to use with  courants