%0 Journal Article %A Alfred K. Louis %T Nonuniqueness in Inverse Radon Problems: The Frequency Distribution of the Ghosts. %J Mathematische Zeitschrift %D 1984 %P 429-440 %V 185 %I mathdoc %U http://geodesic.mathdoc.fr/item/MZ_1984__185_173412/ %F MZ_1984__185_173412