"Frequency" . "This frame element is defined as the number of times an event occurs per some unit of time. A Frequency expression answers the question how often. It is to be distinguished from Iteration, which pertains simply to the number of times an event occurs-Iteration expressions answer the question how many times."@en . "2006-09-05T13:07:20+02:00"^^ . . . "Fre" . . . "10599"^^ . .