(3GdSjGSI h GdMce aj VhA GdOSGJjQ GdebGQfI (B/s - (3CMeO Shjde GdYeQjs ((3GdbGgQI (B:s (3ecJHI GdGfLdh GdeUQjI (B,s, 1950)
. 555-542 (3HHdjhLQGajG(B: (3UaMGJ(B.s
Keywords: (3GdbGfhf GdOSJhQjs