RT Journal Article SR Electronic T1 Determination of Extraction Fraction by a Double-Tracer Method JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 226 OP 230 VO 18 IS 3 A1 Weich, Hellmuth A1 Strauss, H. William A1 D'Agostino, Richard A1 Pitt, Bertram YR 1977 UL http://jnm.snmjournals.org/content/18/3/226.abstract AB