Steven A. Pruess, Estimating the eigenvalues of
Sturm-Liouville problems by approximating the differential equation,
Purdue University, 1970
David S. Dodson (ddodson@kijabe.net),
Optimal order approximation by polynomial spline functions,
Purdue University, 1972
Rong-qing Jia, Spline
interpolation and some related topics, University of Wisconsin-Madison, 1983
Daniel Tien-you Lee (danlee@thu.edu.tw), Some problems in cardinal spline interpolation and approximation, University of Wisconsin-Madison, 1984
Tel : 886-4-23590121 ext 3660
Thomas A. Grandine (thomas.a.grandine@boeing.com),
Computing with multivariate simplex splines, University of Wisconsin, 1985.
Jörg Peters,
Fitting smooth parametric surfaces to 3D data,
University of Wisconsin, 1990.
Thomas James Kunkle (kunklet@cofc.edu),
A multivariate interpolant with $n$th derivatives not much larger than
necessary,
University of Wisconsin, 1991.
Kang Zhao (kangzhao@yahoo.com), Approximation from principal
shift-invariant spaces, University of Wisconsin, 1993.