Averest
   A set of tools for the specification, verification, and implementation of reactive systems. It includes a compiler for synchronous programs, a symbolic model checker, and a tool for hardware/software synthesis. Downloadable in binary form for Linux (i586)
   http://www.averest.org/

Design Methods for Reactive Systems: Yourdon, Statemate, and the UML
   By R.J. Wieringa; Morgan Kaufmann, 2002, ISBN 1558607552. Shows how techniques and approaches of 3 most popular design methods can be mixed in flexible, problem-driven way; more examples on companion website. [Morgan Kaufmann]
   http://books.elsevier.com/us/mk/us/subindex.asp?isbn=1558607552

Lustre
   Declarative synchronous language, kernel language of SCADE (was SAO+/SAGA) industrial environment developed by Esterel Technologies; a description is a set of equations that must be verified always by program variables. [Verimag]
   http://www-verimag.imag.fr/SYNCHRONE/index.php?page=lang-design

SyncCharts
   Graphical formalism (name of model, a syncChart is an instance) dedicated to reactive system modeling. Many features inherited from StateCharts, Argos. Brief introduction, related publications, distribution, downloads.
   http://www.i3s.unice.fr/~map/WEBSPORTS/SyncCharts/

Synchronous Programming Language
   Growing article, with links to many related topics. Wikipedia.
   http://en.wikipedia.org/wiki/Synchronous_programming_language

Synchronous Programming of Reactive Systems
   By Nicolas Halbwachs; Springer, 1993, ISBN 9780792393115. Synthesis of recent works on reactive system design, a term introduced to avoid ambiguities often involved with term realtime. Outline, table of contents, reviews.
   http://www.springer.com/east/home?SGWID=5-102-22-33319353-0

The Esterel Synchronous Programming Language: Design, Semantics, Implementation
   Abstract on paper on reactive kernels making the central, hardest part of reactive systems; Esterel is not full language, it is a program generator used to program reactive kernels as YACC programs parsers from grammars. [ResearchIndex]
   http://citeseer.ist.psu.edu/berry92esterel.html

The Multi-Paradigm Synchronous Programming Language LEA
   To program synchronous reactive systems, made by merging 3 existing synchronous languages (Lustre, Esterel, Argos) by uniform translation rules to a common intermediate format called Boolean automata. Paper, PDF format.
   http://www.ais.fraunhofer.de/~ap/papers/LEA.pdf

The Synchronous Group
   Researches synchronous languages and reactive systems, team at Verimag laboratory, University of Grenoble, France. Presentation, people, research topics, language design, publications, tools.
   http://www-verimag.imag.fr/SYNCHRONE/

The Synchronous Programming Language Signal: A Tutorial
   For this declarative language, for realtime uses: reactive, embedded systems. Synchronous languages are opposite to the asynchronous types, as in C, Ada. Five chapters. Paper, PDF format.
   http://www.irisa.fr/espresso/source/logiciels/SignalPrimer.pdf

Unification of Synchronous and Asynchronous Models for Parallel Programming Languages
   Thesis proposing parallel language, based on C, that lets programmers explicitly specify and manage parallelism on a broad class of architectures. [Purdue University]
   http://cobweb.ecn.purdue.edu/~hankd/CARP/XPC/paper.html