RT Journal Article SR Electronic T1 The Difference between t̄ and t½ JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 759 OP 760 VO 17 IS 8 A1 Michael L. Goris YR 1976 UL http://jnm.snmjournals.org/content/17/8/759.2.abstract AB