The number of edges of the edge polytope of a finite simple graph. - Takayuki Hibi; Aki Mori; Hidefumi Ohsugi; Akihiro Shikama (Ars Math. Contemp., 2016)

The numbers of edges of the order polytope and the chain polytope of a finite partially ordered set. - Takayuki Hibi; Nan Li; Yoshimi Sahara; Akihiro Shikama (Discret. Math., 2017)