1999, Grünbaum, Branko, "Acoptic polyhedra", Advances in discrete and computational geometry (South Hadley, MA, 1996) (PDF), Contemp. Math., 223, Amer. Math. Soc., Providence, RI, pp. 163–199, doi:10.1090/conm/223/03137, MR 1661382. See Norgate [N2], where nonacoptic pentahedra are investigated as well.
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