"Rayons X Découverte." . . "Covers observations and theories leading to Röntgen's work, biographical information about the German physicist, Röntgen's discovery and further research, and improvements and applications of the X ray after the appearance of Röntgen's papers." . . "Wilhelm Conrad Röntgen and the discovery of x rays" . . . . . . . "Wilhelm Conrad Röntgen and the discovery of X rays" . . . . . . .