@article{P077.018,
author={Feys, J.P.R. and De Mey, G. and Claeys, E.G. and Van Der Kelen, G.P.},
title={The field within a commercial EI/FI Source of a mass spectrometer},
journal={Zeitschrift fur Naturforschung},
year={1977},
month={8},
volume={32},
pages={768-774},
}