PT Unknown AU Gershenzon, E Goltsman, G Orlov, L Ptitsina, N TI Population of excited-states of small admixtures in germanium SE Izv. Akad. Nauk SSSR, Seriya Fizicheskaya PY 1978 BP 1154 EP 1159 VL 42 IS 6 DE Ge; excited states; admixtures ER