homology and his work on axiomatic homology theory which had a profound influence on the development of algebraic topology. 1986 Donald E. Knuth for his expository work, The Art of Computer Programming, 3 Volumes (1st Edition 1968, 2nd Edition 1973). 1986 Rudolf E. Kálmán for his two fundamental papers: A new approach to linear filtering and prediction problems, Journal of Basic Engineering, volume 82, (1960), pp. 35–45; and Mathematical description of linear dynamical systems, SIAM Journal on Control and Optimization, volume 1 (1963), pp. 152–192; and for his contribution to a third paper, (with R. S. Bucy) New results in linear filtering and prediction theory, Journal of Basic Engineering, volume 83D (1961), pp. 95–108. 1986 Saunders Mac Lane for his many contributions to algebra and algebraic topology, and in particular for his pioneering work in homological and categorical algebra. 1985 Michael Spivak for his five-volume set, "A Comprehensive Introduction to Differential Geometry" (second edition, Publish or Perish, 1979). 1985 Robert Steinberg for three papers on various aspects of the theory of algebraic groups: Representations of algebraic groups, Nagoya Mathematical Journal, volume 22 (1963), pp. 33–56; Regular elements of semisimple algebraic groups, Institut des Hautes Études Scientifiques, Publications Mathématiques, volume 25 (1965), pp. 49–80; and Endomorphisms of linear algebraic groups, Memoirs of the American Mathematical Society, volume 80 (1968). 1985 Hassler Whitney for his fundamental work on geometric problems, particularly in the general theory of manifolds, in the study of differentiable functions on closed sets, in geometric integration theory, and in the geometry of the tangents to a singular analytic space. 1984 Elias M. Stein for his book, Singular integrals and the differentiability properties of functions, Princeton University Press (1970). 1984 Lennart Carleson for his papers: An interpolation problem for bounded analytic functions, American Journal of Mathematics, volume 80 (1958), pp. 921–930; Interpolation by bounded analytic functions and the Corona problem, Annals of Mathematics (2), volume 76 (1962), pp. 547–559; and On convergence and growth of partial sums of Fourier series, Acta Mathematica volume 116 (1966), pp. 135–157. 1984 Joseph L. Doob for his fundamental work in establishing probability as a branch of mathematics and for his continuing profound influence on its development. 1983 Paul R. Halmos for his many graduate texts in mathematics and for his articles on how to write, talk and publish mathematics. 1983 Stephen Cole Kleene for three important papers which formed the basis for later developments