Nobel prize to W. C. Röntgen awarded in 1901 "for the discovery of the remarkable rays subsequently named after him''
Röntgen, W.C.; Über eine neue Art von Strahlen. Vorlaufige Mitteilung / On a New Kind of Rays. Preliminary Communication
Sitzber. Physik. Med. Ges. 137 (1895) 1;
(translation into English) A Source Book in Physics, Ed. Gregory D. Walcott, McGraw-Hill Book Company, Inc. (1935) 600.
(translation into English) W. R. Nitske, The Life of Wilhelm Conrad Röntgen, University of Arizona Press, Tucson (1971).
(translation into English) The WORLD of the ATOM, editors H. A. Boorse and L. Motz, Basic Books, New York - London, V.I (1966) 389.
If the discharge of a fairly large induction coil be made to pass through a Hittorf vacuum tube, or through a Lenard tube, a Crookes tube, or other similar apparatus, which has been sufficiently exhausted, the tube being covered with thin, black card board which fits it with tolerable closeness, and if the whole apparatus be placed in a completely darkened room, there is observed at each discharge a bright illumination of a paper screen covered with barium platino cyanide, placed in the vicinity
of the induction coil, the fluorescence thus produced being entirely independent of the fact whether the coated or the plain surface is turned towards the discharge-tube. This fluorescence is visible even when the paper screen is at a distance of two metres from the apparatus. It is easy to prove that the cause of the fluorescence proceeds from the discharge apparatus, and not from any other point in the conducting circuit. (Extracted from the introductory part of the paper.).