In addressing the question of who invented the incandescent lamp, historians <answer>Robert Friedel and Paul Israel</answer> list 22 inventors of incandescent lamps prior to Joseph Swan and Thomas Edison. They conclude that Edison's version was able to outstrip the others because of a combination of three factors: an effective incandescent material, a higher vacuum than others were able to achieve (by use of the Sprengel pump) and a high resistance that made power distribution from a centralized source economically viable.
Which historians wrote about the advantages of Edison's lamp over other early versions?
Robert Friedel and Paul Israel