Willard J. Fisher
Phys. Rev. (Series I) 28, 73 (1909) - Published 1 February, 1909
N. F. Smith
Phys. Rev. (Series I) 28, 107 (1909) - Published 1 February, 1909
Edward L. Nichols
Phys. Rev. (Series I) 28, 122 (1909) - Published 1 February, 1909
P. I. Wold
Phys. Rev. (Series I) 28, 132 (1909) - Published 1 February, 1909
T. H. Havelock
Phys. Rev. (Series I) 28, 136 (1909) - Published 1 February, 1909
