Popovici, Nicolae. “ Sur l’approximation Des Ensembles d’efficience: On the Approximation of Efficiency Sets”. Rev. Anal. Numér. Théor. Approx. 27, no. 2 (August 1, 1998): 321–329. Accessed April 14, 2025. https://ictp.acad.ro/jnaat/journal/article/view/1998-vol27-no2-art13.