RT Journal Article SR Electronic T1 Structural Shielding Design and Evaluation for Medical Use of X-Rays & Gamma Rays of Energies Up to 10 meV. NCRP Report No. 49 JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 228 OP 228 VO 19 IS 2 A1 Simmons, Guy YR 1978 UL http://jnm.snmjournals.org/content/19/2/228.abstract AB