Aspects of Combinatorics : A Wide-Ranging Introduction by Victor W. Bryant 1993

An Introduction To Linear Algebra & Tensors

Bridging the Gap to University Mathematics by Edward Hurst and Martin Gould

Elements of Abstract Algebra by Allan Clark (1984 Paperback)

Dover Books on Mathematics Ser.: Proof Theory by Gaisi Takeuti (2013, Paperback)

Set Theory and Logic by Robert R. Stoll (1979, Trade Paperback)

Calculus of Variations by S. V. Fomin and I. M. Gelfand (2000, Trade Paperback)

Logic for Mathematicians by Barrow Mathematics and J. Barkley Rosser paperback