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Vandeghen, A., Mathematical Notes: Soddy's Circles and the De Longchamps Point of a Triangle, The American Mathematical Monthly, 1964, 71 (2): 176–179, MR 1532529, doi:10.2307/2311750.
Coxeter, H. S. M., Some applications of trilinear coordinates, Linear Algebra and its Applications, 1995,, 226/228: 375–388, MR 1344576, doi:10.1016/0024-3795(95)00169-R. See in particular Section 5, "Six notable points on the Euler line", pp. 380–383.
Longuet-Higgins, Michael, A fourfold point of concurrence lying on the Euler line of a triangle, The Mathematical Intelligencer, 2000, 22 (1): 54–59, MR 1745563, doi:10.1007/BF03024448.
doi.org
dx.doi.org
Vandeghen, A., Mathematical Notes: Soddy's Circles and the De Longchamps Point of a Triangle, The American Mathematical Monthly, 1964, 71 (2): 176–179, MR 1532529, doi:10.2307/2311750.
Coxeter, H. S. M., Some applications of trilinear coordinates, Linear Algebra and its Applications, 1995,, 226/228: 375–388, MR 1344576, doi:10.1016/0024-3795(95)00169-R. See in particular Section 5, "Six notable points on the Euler line", pp. 380–383.
Longuet-Higgins, Michael, A fourfold point of concurrence lying on the Euler line of a triangle, The Mathematical Intelligencer, 2000, 22 (1): 54–59, MR 1745563, doi:10.1007/BF03024448.
evansville.edu
faculty.evansville.edu
Kimberling, Clark, X(20) = de Longchamps point, Encyclopedia of Triangle Centers, [2012-09-06], （原始内容存档于2012-04-19）.
