6810 Planimetry. Malfatti's Problem. Nine-point Circle 6810 



In- and ex-circles. Mackay, J. S. Edinb. 



Mth. S. P. 12 (1894) 86-; 13 (1895) 103-. 

 . Billups, H. B. Mth. Gz. 1 (1900) 



177-. 

 (Billups). Mackay, , & Muirhead, 



. Mth. Gz. 1 (1900) 209. 

 of triangles formed by four straight 



lines, Steiner's theorem. Mention, J. N. A. 



Mth. 1 (1862) 16-, 65-. 

 Intersections of circle with triangle, relations. 



Taylor, H. M. L. Mth. S. P. 15 (*1883-84) 



122-. 

 " Intimoscribed " circles. Anderson, E. E. 



Edinb. Mth. S. P. 10 (1892) 70-. 



Malfatti's problem. 



Gergonne, J. D., & Lavernede, . Gergonne 



A. Mth. 1 (1810-11) 343-. 

 Tedenat, . Gergonne A. Mth. 2 (1811-12) 



165. 

 LechmUtz, . Gergonne A. Mth. 10 (1819-20) 



289-. 



Lavernede, T. Gard. Mm. Ac. (1832) 137-. 

 Catalan, E. C. N. A. Mth. 5 (1846) 60-. 

 Ghijben, J. B. Amst. Vs. Ak. 12 (1861) 189-. 

 Talbot, W. H. F. [1865] Edinb. B. S. T. 24 



(1867) 127-. 



Affolter, F. G. Mth. A. 6 (1873) 597-. 

 Simons, P. A. Brux. Ac. Bll. 38 (1874) 88-. 

 Catalan, E. C. Brux. Ac. Bll. 38 (1874) 480-. 

 Pelletreau, . As. Fr. C. R. (1888) (Pt. 2) 



99. 

 Neumann, C. Leip. Mth. Ps. B. 41 (1889) 



22-. 

 extension. Schellbach, C. H. Crelle J. 45 



(1853) 186-. 

 history and complete analytical solution. De- 



rousseau, J. Liege S. Sc. Mm. 18 (1895) 



No. 1, 52 pp. 

 and lemma on circles. Adams, C. N. A. Mth. 



8 (1849) 62-. 

 solution. Scheffler, H. Grunert Arch. 16 (1851) 



424-. 

 . Schellbach, C. H. [1852] N. A. Mth. 12 



(1853) 131-. 



(Schellbach). Cayley, A. QJ. Mth. 1 (1857) 

 222-. 



. Lebon, E. Palermo Cir. Mt. Ed. 3 (1889) 



120-. 

 solutions, thirteen. Davids, C. Arch. Mth. Ps. 



13 (1895)^10-; 14 (1896) 276-. 

 Steiner's construction. Hart, A. S. QJ. Mth. 



1 (1857) 219-. 



, demonstration. Quidde, A. Grunert 

 Arch. 15 (1850) 197-. 



, . Mendthal, . Arch. Mth. Ps. 55 



(1873) 211-. 

 and Steiner's generalisation. Mertens,F. [1875- 



76] Wien. Ak. D. 36 (1876) (Ab. 2) 195- ; 



Z. Mth. Ps. 21 (1876) 297-. 

 . Godt, W. [1877] Crelle J. Mth. 84 



(1878) 259-. 

 . Mertens, F. [1893] Krk. Ak. (Mt.- 



Prz.) Bz. 8 (1895) 67-; Prag Sb. (1894) (Mth.- 



Nt.) No. 1, 21 pp. 

 Steiner's solution. Schroeter, H. E. Crelle J. 



Mth. 77 (1874) 230-. 



Steiner's solution. Petersen, J. Crelle J. Mth. 



89 (1880) 127- 

 , demonstration. Zornow, . Crelle J. 



10 (1833) 300-. 



Neuberg's circles. Gob, A. Liege S. Sc. Mm. 



16 (1890) No. 3, 14 pp. 

 New circle. Fuhrmann, W. Mathesis 10 (1890) 



105-. 



Nine-point or Feuerbach Circle. 



Trudi, N. G. Mt. 1 (1863) 29-. 



Griffiths, J. N. A. Mth. 2 (1863) 339- ; Mess. 



Mth. 2 (1864) 220- ; QJ. Mth. 8 (1867) 15. 

 Besant, W. H. QJ. Mth. 7 (1866) 302- ; Mess. 



Mth. 3 (1866) 222-. 

 Taylor, C. Mess. Mth. 4 (1868) 61-. 

 Hain, E. Arch. Mth. Ps. 59 (1876) 323-. 

 Zeuthen, H. G. (xn) Ts. Mth. 1 (1877) 



113-. 



Lemoine, E. N. A. Mth. 5 (1886) 122-. 

 Wilson, (Eev.) J. Edinb. Mth. S. P. 6 (1888) 



38. 



Cayley, A. Mess. Mth. 23 (1894) 23-, 25-. 

 Sparer, B. Wien Ak. Sb. 106 (1897) (Ab. 2a) 



739-. 

 analytical treatment. Grunert, J. A. Arch. 



Mth. Ps. 41 (1864) 121-. 

 circle analogous to, about centroid of perimeter 



of triangle. Spieker, T. Arch. Mth. Ps. 51 



(1870) 10-. 

 Feuerbach's theorem. Lappe, J. [1869] Crelle 



J. 71 (1870) 387-. 

 . Schroeter, H. E. Mth. A. 7 (1874) 



517-. 

 . Slawyk, R. Z. Mth. Ps. 35 (1890) 



36-. 

 , demonstration. Leudesdorf, C. Mess. 



Mth. 13 (1884) 116-. 

 , . Genese, E. W. L. Mth. S. P. 19 



(1889) 216- . 

 group of circles related to. Baker, M. Smiths. 



Misc. Col. 33 (1888) Art. 3, 45-. (Wash. Ph. 



S. Bll. 8 (1885).) 

 history. Mackay, J. S. Edinb. Mth. S. P. 11 



(1893) 19-. 

 properties of triangle, generalisation. Mac- 



Mahon, P. A. L. Mth. S. P. 14 (1882-83) 



129-. 

 Steiner's hypocycloid and the circumscribing 



hyperbolas of A. Fiedler, W. Ziir. Vjschr. 



30 (1885) 390-. 

 and Steiner's quartic. Godt, W. [1895-96] 



D. Mth. Vr. Jbr. 4 (1897) 161- ; Munch. Ak. 



Sb. 26 (1897) 119-. 

 Terquem's theorem, extension. Hart, A. S. 



QJ. Mth. 4 (1861) 260-. 

 theorems. Salmon, G. QJ. Mth. 4 (1861) 



152- . 

 . Griffiths, J. QJ. Mth. 6 (1864) 357-; 



7 (1866) 46-, 341-. 



Pedal circle of a point with regard to given 

 triangle. Fries, J. de. [1900] Amst. Ak. 

 Vs. 9 (1901) 249-; Amst. Ak. P. 3 (1901) 

 323-. 



444 



