  A star-triangle mapping transformation is used to establish an exact
correspondence between the spin-1/2 Ising model on the Shastry-Sutherland
(orthogonal-dimer) lattice and respectively, the spin-1/2 Ising model on a
bathroom tile (4-8) lattice. Exact results for the critical temperature and
spontaneous magnetization are obtained and compared with corresponding results
on the regular Ising lattices.
