Libby, A., "CLEVELAND SECTION PAPERS ADVANTAGES OF MAGNETO IGNITION," SAE Technical Paper 200062, 1920, doi:10.4271/200062.
A discussion of the advantages of magneto ignition resolves itself into a comparison of magneto and battery-ignition systems, resembling early discussions of the relative merits of the direct and the alternating-current electric systems; both are in existence and fulfilling their respective parts. After stating that ignition is closely related to carburetion and generalizing on the subject of ignition, the author discusses the fundamentals of ignition systems at length, presenting numerous diagrams, and passes to somewhat detailed consideration of comparative spark values, using illustrations.Storage batteries and auxiliary devices receive due attention next and numerous characteristic curves of battery and magneto ignition are shown. Impulse couplings are advantageous in starting large truck and tractor engines, which generally use magnetos; these are described. The degree of spark-advance and flame propagation are treated in some detail and four additional advantages of magneto over battery ignition are specifically stated in conclusion.