Lowell, Constance S., Discovery of Pluto
Lowell Prize at the Normal School (Northern Arizona University)
Letter from Constance Lowell (Mrs. Percival) to Carl Lampland, March 9, 1930, 1930-03-09
Roger Putnam has written Mrs. Lowell about the observation of what may be Planet X and if she has any thoughts about the naming thereof.
Tombaugh, Clyde W., Credit for the discovery of Pluto
The Martian Polar Cap "Carbonic Acid" hypothesis
Letter from Clyde Tombaugh to Carl Lampland, November 1, 1932, 1932-11-01
Professor Baker's book and credit for the discovery of Pluto. Rock salt crystals for prism purposes. Dry ice, Martian polar caps, carbon dioxide…
Flammarion, Gabrielle Camille, Discovery of Pluto
Telegram from Gabrielle Camille Flammarion (Directrice Observatoire de Juvisy) to Carl Lampland, March 24, 1930, 1930-03-24
Congratulations on TransNeptunian planet discovery
Lampland, Carl O., Discovery of Pluto
Idea of a group of transneptunian planets
Letter from Carl Lampland to Gabrielle Camille Flammarion, November 17, 1930, 1930-11-17
Gabrielle Camille Flammarion's idea of a group of transneptunian planets
Discovery plates of Pluto sent to Gabrielle Camille Flammarion
Clemence, G.M, Pluto orbit work
Letter from G.M. Clemence (Director of the Nautical Almanac Office, part of the U.S. Naval Observatory) to Carl Lampland, February 16, 1948, 1948-02-16
Valuable series of observations of Pluto by Carl Lampland as described by Dr. Oort.
G.M. Clemence and Dr. Brouwer are engaged in a research program…