An isosceles triangle that tiles the sphere in exactly three ways
The \((80^\circ,60^\circ,60^\circ)\) spherical triangle tiles the sphere, through not in an edge-to-edge fashion. It is shown that it tiles in exactly three different ways. See also the author's paper in ibid. 30, No. 3, 467--487 (2003; Zbl 1053.52027).
scientific article; zbMATH DE number 2078221