OBM 1987 Problem 4

Given points $A_1 (x_1, y_1, z_1), A_2 (x_2, y_2, z_2), .., A_n (x_n, y_n, z_n)$ let $P (x, y, z)$ be the point which minimizes $\Sigma ( |x - x_i| + |y -y_i| + |z -z_i| )$ . Give an example (for each $n > 4$ ) of points $A_i$ for which the point $P$ lies outside the convex hull of the points $A_i$ .