where the first expression uses the basis of Conway et al. (1999). It can be dissected into the square
gyrobicupola, from which it differs only by the relative rotation of the top
and bottom cupolas.
Conway, J. H.; Radin, C.; and Sadun, L. "On Angles Whose Squared Trigonometric Functions Are Rational." Discr. Computat. Geom.22,
321-332, 1999.Johnson, N. W. "Convex Polyhedra with Regular
Faces." Canad. J. Math.18, 169-200, 1966.