J. Mike Spivey; Prentice Hall, International Series in Computer Science, 1988, 1992, 2001, ISBN 0139785299. Standard reference work for Z. Description, free downloads: PostScript, PDF, LaTeX. [University of Oxford]
By Jim Woodcock, Jim Davies; Prentice Hall, 1996, ISBN 0139484728. Treats formal techniques and methods for software engineering via Z. Full text, slides, exercises, solutions, cards, contents. [University of Oxford, Online]
By Jonathan Jacky; Cambridge University Press, 1997, ISBN 0521559766. Introduces formal methods (FM) via Z, case studies, tutorial, glossary. [University of Washington]
By Graeme Smith; Kluwer Academic Publishers, 2000, ISBN 0792386841. Textbook or reference, fully describes topic: semantics, defines all constructs, type and usage rules, specification guidelines, full syntax. [University of Queensland]
By Ben Potter, Jane Sinclair, David Till; Prentice Hall PTR, 1997, ISBN 0132422077, 2nd edition. For developers; Z notation can greatly improve the way software systems are modeled, implemented; investigate specifications before construction. [Prentic...
Edited by Susan Stepney, Rosalind Barden, David Cooper; Springer-Verlag, 1992, ISBN 3540197788. Set of papers showing many ways to add OO concepts and structuring to Z. Each shows same problems, for comparing. [University of York]