The three main sources for first ascent data are: For the Western Alps; W.A.B. Coolidge, The Alps in nature and history, Methuen & Co, London, 1908. For the Central Alps; Gottlieb Studer, Über Eis und Schnee: Die höchsten Gipfel der Schweiz und die Geschichte ihrer Besteigung, Volumes 1-3, Schmid & Francke, Bern, 1896-1899. For the Eastern Alps: Die Erschließung der Ostalpen, Volumes 1-3, German and Austrian Alpine Club, Berlin, 1894. Given are the years for the first recorded ascents. In many cases local people or surveyors made earlier ascents. In particular, chamois and ibex hunters are expected to have reached many summits. Years in italics indicate that it is known that an earlier ascent was made, for example by the presence of artifacts on top or the summit's prior use as a triangulation point.
