$1'`[!C[!>['H|!9B!1?'2>(B: $1'6o!G4(B. $1!DK'2Fs - $1!:g!=u!3W(B. $1!U+!GE!^s!UN(B; $1!\g'QN!>#!Oz'YFs ($1!H#!4c!0d!FM!3K!JH!Nas, 1986)