Brout and Englert showed in 1964 that gauge vector fields, abelian and non-abelian, could acquire mass if empty space were endowed with a particular type of structure that one encounters in material systems. Focusing on the failure of the Goldstone theorem for gauge fields, Higgs reached essentially the same result. A third paper on the subject was written later in the same year by Gerald Guralnik, C. R. Hagen, and Tom Kibble. The three papers written on this boson discovery by Higgs, Englert and Brout, and Guralnik, Hagen, Kibble were each recognized as milestone papers for this discovery by Physical Review Letters 50th anniversary celebration. While each of these famous papers took similar approaches, the contributions and differences between the 1964 PRL symmetry breaking papers is noteworthy.