Combinatorial fans, lattice-ordered groups, and their neighbours: A short excursion. Marra, Vincenzo; Mundici, Daniele — 2002 Séminaire Lotharingien de Combinatoire [electronic only]
Riemann average truth-value of Łukasiewicz formulas Vincenzo Marra; Daniele Mundici — 2006 Mathematica Slovaca