1. W.R. Hamilton, On a new species of imaginary quantities connected with the theory of quaternions, in: Halberstam and Ingram [18], pp. 111–116 (Chapter 5). First published as [2]
2. On a new species of imaginary quantities connected with the theory of quaternions;Hamilton;Proceedings of the Royal Irish Academy,1844
3. Quaternions and Cayley Numbers: Algebra and Applications;Ward,1997
4. Introduction to Quadratic Forms;O’Meara,1963
5. W.R. Hamilton, Researches respecting quaternions. First series (1843), in: Halberstam and Ingram [18], pp. 159–226 (Chapter 7). First published as [6]