Abstract
In the paper by Salpeter and Szabo entitled "Sensitivity in Electron Microscope Autoradiography. I. The Effect of Radiation Dose," which appeared in the June issue of the Journal (Vol. 20, pp. 425-434, 1972), the lines 28 and 29 of column 2 on page 427 should read, "2. In a second method, sections of tritiated methacrylate (10 mC/g or 400 µC/g) were used...."