New spherical PET design with fresnel aperture orientation. - Zang Hee Cho; Y. S. Kim; Sadek K. Hilal; Y. H. Kim (Int. J. Imaging Syst. Technol., 1989)

Weighted backprojection approach to cone beam 3D projection reconstruction for truncated spherical detection geometry. - Zang Hee Cho; Ed X. Wu; Sadek K. Hilal (IEEE Trans. Medical Imaging, 1994)