Addendum [to "Fundamentals of Electromagnetic Units and Constants"]

Since the article by K.T. Selvan, "Fundamentals of Electromagnetic Units and Constants" (IEEE Antennas and Propagation Magazine, Vol 54, no 3, June 2012, pp. 100-114) appeared in print, two relevant previous papers have come to the author's attention and are note here. Leo Young's article (2002) presents an interesting discussion, with examples, of conversion and comparison between different systems of electromagnetic units. The more recent article by Pelosi and Sellari (2010) provides a historical account of the measurement and naming of the velocity of light, c.