The definitive guide to using REDUCE, namely the REDUCE User's Manual, and other user guides are distributed with REDUCE and also available online for free. In addition, the following independently published books are available, sorted by publication date from newest to oldest. (They should also be included in the bibliography, but can be hard to find there.) Links are to the publisher if possible or otherwise to a bookseller such as Amazon.

Books primarily about REDUCE

Using REDUCE in High Energy Physics by A. G. Grozin 404 pages, Cambridge University Press, ISBN 9780521019521, 2005 (See also the author's own web page.)
REDUCE Ein Kompaktkurs über die Anwendung von Computer-Algebra by Friedrich W. Hehl, Volker Winkelmann and Hartmut Meyer 143 pages, Springer, ISBN 9783540567059, 1993
Einführung in die Computeralgebra mit REDUCE für Mathematiker, Informatiker und Physiker by Johannes Ueberberg 331 pages, BI-Wiss.-Verlag, ISBN 9783411157815, 1992
Computer Algebra with LISP and REDUCE An Introduction to Computer-aided Pure Mathematics by F. Brackx and D. Constales 264 pages, Springer, ISBN 9789401055499, 1991
Algebraic Computing with REDUCE by Malcolm A. H. MacCallum and Francis J. Wright 314 pages, Oxford University Press, ISBN 9780198534433, 1991
REDUCE Software for Computer Algebra by Gerhard Rayna 329 pages, Springer, ISBN 9780387965987, 1987

Books that include information about, or closely related to, REDUCE

Computer Algebra Handbook Foundations · Applications · Systems edited by Johannes Grabmeier, Erich Kaltofen and Volker Weispfenning 637 pages, Springer, ISBN 9783642629884, 2003
Quantum Mechanics Using Computer Algebra Includes Sample Programs for REDUCE, MAPLE, MATHEMATICA and C++ by Willi-Hans Steeb 200 pages, World Scientific, ISBN 9789810217709, 1994
Computer Simulation and Computer Algebra Lectures for Beginners by D. Stauffer, Friedrich W. Hehl, Nobuyasu Ito, Volker Winkelmann and John G. Zabolitzky 287 pages, Springer, ISBN 9783540565307, 1993
RLISP '88 An Evolutionary Approach to Program Design and Reuse by Jed Marti 268 pages, World Scientific, ISBN 9789810214791, 1993
Computer Algebra Systems and Algorithms for Algebraic Computation by J. H. Davenport, Y. Siret and E. Tournier 256 pages, Academic Press, second edition, ISBN 0122042301, 1993