the form



This expression, in turn, is equivalent to
sin x §B= sin ?A sin 1C,
of which triangle (1) is a special case."


I obtained references 1, 2 from [157; references 3, 7, 9, 17 from [2o1; reference 4 from [51; reference 6 from [11 J; reference 8 from [147; reference 10 from [167; reference 12 from [131; all the remaining references are my own.

REFERENCES





3. J. J. Sylvester, On a simple geometrical problem illustrating a conjectured principle in the theory of geometrical method, Philosophical Magazine, Vol. u, 1852, pp. 366 - 369.





7. A. Henderson, A classic problem in Euclidean geometry, J. Elisha Mitchell Soc., 1937, pp. 246 - 281.

9. J. A. McBride, The equal internal bisectors theorem, Edinburgh Mathematical Notes, Vol. 33, 1943, pp. 1 -13.
10. V. Thebault, The Theorem of Lehmus, Scripta Mathematica, Vol. 15, 1949, pp. 87 - 88.


13. G. Gilbert and D. McDonnell, The Steiner-Lehmus Theorem, American Mathematical. Monthly, Vol. 70, 1963, pp. 79-80.
14. H. S. M. Coxeter, S. L. Greitzer, Geometry Revisited, Random House of Canada, 1967, pp. 14 - 16, 156.


17. J. V. Malesevic, A direct proof of the Steiner-Lehmus Theorem, Mathematics Magazine, Vol. 43, 1970, pp. 101 - 102.