(3GdbGfhf GdOSJhQj (B: s (3hJWhQ GdCfXeI GdOSJhQjI aj eUQ (B/s - (3KQhJ HOhjs ((3GdbGgQI (B: s (3OGQ GdfgVI GdYQHjI , s, 1971)
(3GdfU HGddZI GdYQHjIs
Keywords: (3GdfXGe GdOSJhQj s; (3GdbGfhf GdOSJhQj s