Does 𝐒𝐏 K ⊇ 𝐏𝐒 K imply axiom of choice? Hajnal Andréka, István Németi (1980) Commentationes Mathematicae Universitatis Carolinae
Dualities associated to binary operations on R ¯ . Martínez-Legaz, Juan-Enrique, Singer, Ivan (1995) Journal of Convex Analysis