diary-make-date
diary-make-date is a compiled Lisp function in `diary-lib.el
'.
(diary-make-date A B C)
Convert A B C into the internal calendar date form.
The expected order of the inputs depends on `calendar-date-style',
e.g. in the European case, A = day, B = month, C = year. Returns
a list (MONTH DAY YEAR), i.e. the American style, which is the
form used internally by the calendar and diary.