Stephen B. Gray: Generalizing the Petr-Douglas-Neumann Theorem on N-Gons. In: The American Mathematical Monthly, Band 110, Nr. 3, März 2003, S. 210–227 (JSTOR)
Christoph J. Scriba: Wie kommt 'Napoleons Satz' zu seinem namen? In: Historia Mathematica. Band8, Nr.4, 1981, S.458–459, doi:10.1016/0315-0860(81)90054-9.
google.de
books.google.de
Claudi Alsina, Roger B. Nelsen: Perlen der Mathematik: 20 geometrische Figuren als Ausgangspunkte für mathematische Erkundungsreisen. Springer, 2015, ISBN 978-3-662-45461-9, S. 90–91
jstor.org
Stephan Berendonk: A Napoleonic Theorem for Trapezoids. In: The American Mathematical Monthly, Vol. 126, No. 4, April 2019, S. 367–369 (JSTOR)
Branko Grünbaum: Is Napoleon’s Theorem Really Napoleon’s Theorem? In: The American Mathematical Monthly. Band 119, Nr. 6 (Juni‒Juli 2012), S. 495–501 (online, JSTOR)
ox.ac.uk
dbooks.bodleian.ox.ac.uk
Dublin problems: a collection of questions proposed to the candidates for the gold medal at the general examinations, from 1816 to 1822 inclusive. Which is succeeded by an account of the fellowship examination, in 1823. G. and W. B. Whittaker, London 1823 (online, 22,8 MB)
washington.edu
faculty.washington.edu
Branko Grünbaum: Is Napoleon’s Theorem Really Napoleon’s Theorem? In: The American Mathematical Monthly. Band 119, Nr. 6 (Juni‒Juli 2012), S. 495–501 (online, JSTOR)