J. van Eck, F.J. de Heer and J. Kistemaker: Interaction of Li+ ions with H2 and He in the energy range of 5 to 25 keVIn: Proceedings Fifth International Conference on Ionization Phenomena in Gases, Munich 28 August - 1 September 1961, Vol. 1 /ed. H. Maecker, North-Holland, 1962. - pp. 54-59
N.A.I.M. Boelrijk, Ion-molecule reactions and charge transfer in the ionization chamber of the mass spectrometer, University of Amsterdam UvA, 1961-04-19
A.E. de Vries: Some chemical problems connected with the electro-magnetic separation of isotopesIn: Electromagnetic Separation of Radioactive Isotopes : Proceedings of the International Symposium held in Vienna, May 23-25, 1960 /ed. M.J. Higatsberger and F.P. Viehb, Cham: Springer, 1961. - pp. 250-256