$1!C!KGa'2F!92!BB!0Ps - $1!S;!\c(RR!+5!K3!F]';5!+5'4"!5"!Ols ($1!04!<5!5.!PN!3K!JH!Nas, 1987)
Keywords: $1!;E'Xi(B--$1'Oy'X<(B; $1'L4'Rqs