?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adissertation&rft.au=Cullum%2C+Ian+Derek&rft.aufirst=Ian+Derek&rft.aulast=Cullum&rft.date=1994&rft.title=The+application+of+Monte+Carlo+simulation+to+the+design+of+collimators+for+single+photon+emission+computed+tomography&rft.inst=UCL+(University+College+London)&rft.tpages=182&rft.degree=Doctoral