TY - JOUR AU - Poerschke, R. AU - Wollenberger, H. TI - A helium-cooled magnetic amplifier for d c measurements in the picovolt range JO - Cryogenics : low temperature engineering, applied super conductivity, cryoelectronics, cryophysics VL - 10 IS - 4 SN - 0011-2275 CY - Amsterdam PB - Elsevier M1 - RWTH-CONV-011168 SP - 333-335 PY - 1970 LB - PUB:(DE-HGF)16 UR - <Go to ISI:>//WOS:A1970G901400015 DO - DOI:10.1016/0011-2275(70)90067-6 UR - https://publications.rwth-aachen.de/record/129994 ER -