T. Peczalski
Phys. Rev. 11, 363 (1918) - Published 1 May, 1918
P. S. Helmick
Phys. Rev. 11, 372 (1918) - Published 1 May, 1918
Leigh Page
Phys. Rev. 11, 376 (1918) - Published 1 May, 1918
Clayton T. Ulrey.
Phys. Rev. 11, 401 (1918) - Published 1 May, 1918
Q. Majorana
Phys. Rev. 11, 411 (1918) - Published 1 May, 1918