Sure, it was from a three-part discussion of hyperdimensional physics by Richard Hoagland. The specific part involving quaternions were in a description of the reduction of Maxwell's equations, where there was no recognition of the energy potentials of scalar componants, versus that of vector componants, leading to the scalar componants being factored out in a "reduction" of the number of equations.
Hoagland's work is, as I am sure you are aware, the subject of a lot of argument over it's validity. Nevertheless I have found him to be a source of a lot of information that is otherwise refused acknowledgement. And he's been shown to be right more times than not, to the consternation of NASA.
Anyway, if it's your cup of tea, Cheers!
http://www.enterprisemission.com/hyper1.html
http://www.enterprisemission.com/hyper1a.html
http://www.enterprisemission.com/hyper2.html
http://www.enterprisemission.com/hyper2a.html
http://www.enterprisemission.com/hyper3.html
The problem with Hoagland is that he’s loaded down with 01100010 01110101 01101100 01101100 00100000 01110011 01101000 01101001 01110100