(3MQjI GdeGdjI (B: s (3ESJQGJjLjI ESJKeGQjg eHSWg ddCaQGO (B/ s - (3UHM, eMehOs ([(3ZjQ eYQa(B] :s [(3ZjQ eYQa(B](3, s, 1999)
Keywords: (3GdESJKeGQ(B. s; (3GdEbJUGO(B. s; (3GdeGdjI(B. s; (3GdEOGQI GdeGdjI(B. s