“Procedures in External Radiation Therapy Dosimetry With Electron and Photon Beams With Maximum Energies Between 1 and 50 MeV Recommendations by the Nordic Association of Clinical Physics (NACP)”. Acta Oncologica, vol. 19, no. 1, Jan. 1980, pp. 55-79, doi:10.3109/02841868009130136.