(3JHSjW GOGH GdcHGQ ddGWaGd (B: s (3OQGSI fXQjI eY feGPL JMdjdjI (B/ s - (3SgjQ GMeO eMahXs ((3GdbGgQI (B: s (3GdgjFI GdeUQjI GdYGeI ddcJGH , s, 1991)
Keywords: (3GdGOH GdYQHis; (3cJH GdGWaGds; (3GOH GdGWaGd (B- (3JGQjN hfbOs