EM-IntraSPECT algorithm with ordered subsets (OSEMIS) for nonuniform attenuation correction in cardiac imaging. - Andrzej Król; Ifeanyi Echeruo; Roberto B. Solgado; Amol S. Hardikar; James E. Bowsher; David H. Feiglin; Frank Deaver Thomas; Edward Lipson; Ioana L. Coman (Image Processing, 2002)