The solution of the EMFL problem with two new facilities in a quadrangle

This paper is concerned with the analytical solution of the EMFL (Euclidean multifacility location) problem with two new facilities and four existing facilities. In Section 1, the optimality conditions for a general EMFL problem are summarized in the form presented in 1]. In Section 2, they are applied to the considered problem, in order to locate the new facilities and to partition the space of the weights (for a given set of existing facilities) into regions with the same type of solution. However, it is pointed out that a complete solution can be obtained only in particular cases.