Eric Dollard, 22-3-2015:
"Charles Proteus Steinmetz's original math model is a natural outgrowth of Nikola Tesla's polyphase power systems. Tesla was the discoverer, but Steinmetz was the builder who first applied Versor Algebra to the analysis of alternating current power systems.
In my presentation and book FOUR QUADRANT REPRESENTATION OF ELECTRICITY,
my extension of Steinmetz's work is presented in the most simple way possible using very simple analogies, pictures and diagrams. It was a very difficult task as the goal was to facilitate an understanding for the layman.