source 2008 Bernstein--Lange--Rezaeian Farashahi appliesto wz-1 compute A = W2 W3 compute B = Z2 Z3 compute C = (W2+Z2)(W3+Z3) compute W5 = Z1(d1(C+A+B)^2) compute Z5 = W1(A C+d1 B^2)