1. O. Heaviside, The Electrician XXII, 83?84 (1888?1889). This paper is also published in Electrical Papers Vol. II pp. 492?494.
2. O. Heaviside, The Electrician XXII, 147?148 (1888?1889). This paper is also published in Electrical Papers Vol. II pp. 494?496.
3. O. Heaviside, Phil. Mag. (Fifth series) XXVII, 324?339 (1889). This paper is also published in Electrical Papers Vol. II pp. 504?518, where, on page 516, there has been added an important footnote about a renewed investigation concerning particles with velocities greater than light, which Heaviside had started in 1890.
4. J. J. Thomson, Phil. Mag. (Fifth series) XXVIII, 1?14 (1889). See in particular pp. 13?14.
5. O. Heaviside, The Electrician XXIII, 458?459 (1889). This paper is also published in Electrical Papers Vol. II pp. 496?499.