Charles W. Waidner and Francis Mallory
Phys. Rev. (Series I) 8, 193 (1899) - Published 1 April, 1899
Barry Mac Nutt
Phys. Rev. (Series I) 8, 237 (1899) - Published 1 April, 1899
Carl Kinsley
Phys. Rev. (Series I) 8, 244 (1899) - Published 1 April, 1899
Leopold Kann
Phys. Rev. (Series I) 8, 250 (1899) - Published 1 April, 1899