RT Journal Article SR Electronic T1 Channel Ratio in the Determination Of Two Gamma-Emitting Radioisotopes JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 562 OP 564 VO 5 IS 7 A1 Spencer, Richard P. A1 Seife, Burton YR 1964 UL http://jnm.snmjournals.org/content/5/7/562.abstract AB