(3eYLe GdCdaGX GdeKfGI (B((3GdeKfjGf (B) / s - (3GdCejf, TQja jMjis ((3HjQhJ (B:s (3OGQ GdYde dedGjjf,s, 1990)
Keywords: (3GddZI GdYQHjIs; (3GdeYGLe GdeJNUUIs