(declare-function calendar-hebrew-date-string "cal-hebrew" (&optional date))
(declare-function calendar-islamic-date-string "cal-islam" (&optional date))
(declare-function calendar-iso-date-string "cal-iso" (&optional date))
-(declare-function calendar-iso-from-absolute "cal-iso" (&optional date))
+(declare-function calendar-iso-from-absolute "cal-iso" (date))
(declare-function calendar-julian-date-string "cal-julian" (&optional date))
(declare-function calendar-mayan-date-string "cal-mayan" (&optional date))
(declare-function calendar-persian-date-string "cal-persia" (&optional date))