Electron impact differential and integral cross sections for excitation of the n = 2 states of helium at 29.2 eV, 39.2 eV and 48.2 eV R.I. Hall, G. Joyez, J. Mazeau, J. Reinhardt et C. SchermannJ. Phys. France, 34 10 (1973) 827-843DOI: https://doi.org/10.1051/jphys:019730034010082700
