Rolf Färe, Carl Pasurka, Michael Vardanyan. On endogenizing direction vectors in parametric directional distance function-based models.
European Journal of Operational Research, Elsevier, 2017, 262 (1), pp.361 - 369.
⟨10.1016/j.ejor.2017.03.040⟩.
⟨hal-01744614⟩ 
