TY - JOUR T1 - Characteristic Frequency and Atomic Number JF - Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character (1905-1934) VL - 94 IS - 657 SP - 100 EP - 111 PY - 1917/12/01/ UR - http://dx.doi.org/10.1098/rspa.1917.0052 M3 - doi:10.1098/rspa.1917.0052 AU - Allen, H. ER -