Remove all of the grammar problems from this.
Some historians claim there were 20 over inventors of incandescent lamps prior to Edison's version but Edison is often credited with the invention because his version was able to outstrip the earlier versions because of a combination of three factors: "an effective incandescent material, a higher vacuum than others were able to achieve and a high resistance that made power distribution from a centralized source economically viable."
Some historians claim there were 20 other inventors of incandescent lamps prior to Edison's version, but Edison is often credited with the invention because his version was able to outstrip the earlier versions because of a combination of three factors: "an effective incandescent material, a higher vacuum than others were able to achieve and a high resistance that made power distribution from a centralized source economically viable."