M.H. de Vasconcelos, F. Cannemeijer and A.E. de Vries, The choice of a calibration gas for CH4 spectrophone measurements: NH3 or a small amount of C2H6 in CH4, Chem. Phys. Lett. 12, 154-156 (1971)
J.F.M. Aarts and F.J. de Heer, Emission cross sections for 0 I and 0 II multiplet radiation produced by electron impact on O2, Physica 56, 294-296 (1971)
A.J.H. Boerboom, H. van Dop and J.H. Los, Elastic scattering of particles with noble gas electron configuration in the energy range from 150 through 4000 eV, Physica 46, 458-468 (1970)