erc: who: Rueppel, D. W. what: Microprocessor-controlled portable neutron spectrometer when: 19790829 where: https://digital.library.unt.edu/ark:/67531/metadc1095447/ erc-support: who: University of North Texas Libraries what: Permanent: Stable Content: when: 20081203 where: https://digital.library.unt.edu/ark:/67531/