General Articles

		"report of a French commission about the exhibition in London 1851" (in French) source: V.Monnier

	Bölter, D.	Der Zehnerübertrag in Scheibenaddierern the tens carry mechanism in disk adders

	Chase, George C.	History of Mechanical Computing Machinery IEEE Annals of the History of Computing Vol 2, No.3 July 1980 by courtesy of Monroe Calc. Comp.

	Detlefsen, Max	Polnische Rechenmaschinenerfinder des 19. Jahrhunderts Wissenschaft und Fortschritt, 26 (1976), pages 86 - 90 Polish inventors of calculators in the 19th century

	Galle, A.	Mathematische Instrumente Leipzig, 1912 source: Google

	Horsburgh, E. M.	Modern Instruments and Methods of Calculation a handbook of the Napier Tercentenary Exhibition, 1914

	Mehmke, R.	Numerisches Rechnen Stuttgart, 1902 Göttinger Digitalisierungszentrum

	d'Ocagne, M.	Le Calcul Simplifié Paris, 1905 (in French) source: Google

	Robinson, C.	Notes on Binary Decimal and Decimal Binary Conversion (using Brunsviga)

	Turck, J.A.V.	Origin of Modern Calculating Machines Chicago, 1921 source: Google

	Bruce O.B. Williams and Roger G. Johnson	Why are tabular calculators almost forgotten? Birkbeck College University of London