`- 191 -`

`
`
`cds `
= h , b
*d = a(c+s), *P3(E) = P3 (F),

`and`

*a+ s *
= a , b
*d = c(a *
`+s), P3(E) = P3(G).`

`Thus P3 (E) = P3(F) = P (G), and 0F0' follows from 1(d). Hence ON= OM and the proof is complete.`

`
`
`A BIBLIOGRAPHY OF THE STEINER-LEHMUS THEOREM`

`
`
`CHARLES W. TRIGG, Professor Emeritus, Los Angeles City College`

`The following references to the Steiner-Lehmus Theorem and related theorems will serve
to augment the bibliography given by Sauv6 in `*EUREKA (1976: 23-241.*

*1. The American Mathematical Monthly, 2 (1895), 157, 189-91; 3 *(March *1896), 90; 5
*(April *1898), 1o8; 9 *(Feb. *1902), 43; 15 *(Feb. *1908), 37; 24 *(Jan. *1917), 33; 24 *(Sept. *1917),
344; 25 (1918), 182-3; 40 *(Aug. *1933), 1123.*

*
*
*2. The Mathematics Teacher, 45 *(Feb. *1952), 121-2.
*

*
*

*
*
*3. Mathematical Gazette, *Dec.
*1959.
*

*
*

*
*
*4. School Science and Mathematics, 6 *(Oct. *1906), 623; 18 *(May *1918), 1163.
*

*
*

*5. *Richard Philip Baker, *The Problem of the Angle-Bisectors, *University of Chicago
Press, *98 *pages (Circa *1911). O.P.*

*6. *W.E. Bleick, "Angle Bisectors of an Isosceles Triangle," *American Mathematical. Monthly,
55 *(Oct. *1948), 495.*

*7. *W.E. Buker, (Equal external bisectors), Solution of problem *E305, American
Mathematical Monthly, 45 *(August *1938), 480.*

*8. *Lu Chin-Shih, (Equal external bisectors), Solution of problem *1148, School Science
and Mathematics, 31 *(April *1931), 465-466.*

*9. *Sister Mary Constantia, "Dr. Hopkins' proof of the angle bisector problem," *The
Mathematics Teacher, 57 *(Dec. *1964), 539-541.*

`1o. J.J. Corliss, "If Two External Bisectors are Equal is the Triangle Isosceles?" `*School
Science and Mathematics, 39 *(Nov. *1939), 732-735.*

*
*
`11. N.A. Court, `*College Geometry, *Johnson Publishing Co., *(1925), p. 66.
*

*
*

*12. *A.W. Gillies, A.R. Pargetter, and H.G. Woyda, "Three notes inspired by the SteinerLehmus Theorem," *Mathematical Gazette, 57 *(Dec. *1973), 336-339.*

*13. *William E. Heal, "Relating to the Demonstration of a Geometrical Theorem," *American
Mathematical Monthly, 25 (1918), 182-183.*

*14. *Archibald Henderson, "The Lehmus-Steiner-Terquem Problem in Global Survey," *Scripta
Mathematica, 21 (1955), 223, 309.*

*
*