Ben-Ayed, Omar; Boyce, David E.; Blair, Charles E. - In: Transportation Research Part B: Methodological 22 (1988) 4, pp. 311-318
A formulation of the network design problem as a bilevel linear program is presented which admits both the convex and concave investment functions. It also allows a more general representation of travel cost functions than a previous formulation by LeBlanc and Boyce (1986).