prof. emer. math.
New Mexico State University
Constructive Geometry
Constructive projective geometry, in Handbook of Constructive Mathematics, ed., D. Bridges, et al, Encyclopedia Math. Appl., 185, Cambridge University Press, 2023, Chapter 7, pp. 168-198. preprint arXiv
Constructive harmonic conjugates, Beitr. Algebra Geom. 60 (2019), 391–398. pdf doi
A constructive version of the Sylvester-Gallai Theorem, Acta Math. Hungar. 150 (2016), 121-130. pdf doi
A constructive real projective plane, J. Geom. 107 (2016), 19-60. pdf doi
- Correction: see Constructive harmonic conjugates, above.
Constructive projective extension of an incidence plane, Trans. Amer. Math. Soc. 366 (2014), 691-706. pdf
The common point problem in constructive projective geometry, Indag. Math. (N.S.) 24 (2013), 111–114. pdf
Constructive coordinatization of Desarguesian planes, Beiträge Algebra Geom. 48 (2007), 547-589. pdf
Constructive Mathematics
Constructive mathematics, Math. Mag. 58 (1985), 272-280. (expository) pdf doi arXiv
Brouwerian counterexamples, Math. Mag. 62 (1989) 3-27. (expository/survey) pdf doi
Constructive Analysis
Connectivity of an interval, Proc. Amer. Math. Soc. 54 (1976), 170-172. pdf
An example in connectivity, Bull. London Math. Soc. 10 (1978), 314. pdf
Suprema of located sets, J. London Math. Soc. (2) 20 (1979), 161-164. pdf
Resolutions on the line, Pacific J. Math. 88 (1980), 91-100. pdf
Located sets on the line, Pacific J. Math. 95 (1981), 401-409. pdf
Continuity of monotone functions, Pacific J. Math. 99 (1982), 413-418. pdf
Components of an open set, J. Austral. Math. Soc. (Series A) 33 (1982), 249-261. pdf
Constructive Continuity, Memoirs Amer. Math. Soc. 42, nr.277, 1983.
Constructive irrational space, Manuscripta Math. 60 (1988), 397-406. pdf MR
Constructively complete finite sets, Z. Math. Logik Grund. Math. 34, (1988), 97-103.
Limited omniscience and the Bolzano-Weierstrass principle, Bull. London Math. Soc. 20 (1988), 319-320. pdf
Metrization of the one-point compactification, Proc. Amer. Math. Soc. 107 (1989) 1111-1115. pdf
Open subspaces of locally compact metric spaces, Math. Logic Quart. 39 (1993), 213-216. pdf
Finitary sequence spaces, Math. Logic Quart. 39 (1993), 416-430. pdf
Convexity and osculation in normed spaces, Rocky Mountain J. Math. 43 (2013), 551-561. pdf
Topological Spaces
On the uniform continuity of Tietze extensions, Arch. Math. (Basel) 55 (1990), 387-388.
A short proof of the Tietze-Urysohn Extension Theorem, Arch. Math. (Basel) 60 (1993), 364-366.
Lattice Theory
Relative annihilators in lattices, Duke Math. J. 37 (1970), 377-386.
Rings of Continuous Functions
Prime z-ideal structure of C(R), Fund. Math. 63 (1968), 145-166. (dissertation) pdf
Prime ideal structure of rings of bounded continuous functions, Proc. Amer. Math. Soc. 19 (1968), 1432-1438. pdf
F'-spaces and z-embedded subspaces, Pacific J. Math. 28 (1969), 615-621.
Round z-filters and round subsets of ßX, Israel J. Math. 7 (1969), 1-8. pdf
Supports of continuous functions, Trans. Amer. Math. Soc. 156 (1971), 73-83. pdf
Separating chains in topological spaces, J. London Math. Soc. (2) 4 (1972), 510-512. (with D. G. Johnson)
Functions with pseudocompact support, Gen. Topology Appl. 3 (1973), 331-338. (with D. G. Johnson)
Round sets, Symposia Mathematica, vol. 17, Rome, 1976, 43-48.
Euclidean Geometry
The Altitudes of a Triangle, Amer. Math. Monthly 131 (2024), 162-163. doi
Revision, with minor update in the proof: pdf arXiv
Book review
Thinking about Analysis pdf
Photo 1984
b. 1933, Wisconsin, USA
1962-64, SUNY, Stony Brook
1966-69, University of Kansas
1969- ... , New Mexico State University