– ?????: ???? ??????? ????????, ???? ???? ???? ????? ?? ???? ????? ????? ????? ??? ??????? ? ???? ??? ????? ?????? ??????? ? ???????? ????? ? ????? ??????? ??? ??????? ? ????? ????????? ???? ???? ????? ?? ???????* In the course of the seventies these factors revolutionized Digital sign