. Fig, An execution augmented with causal information. Numbers refer to the events of Figure 4. represent data causes, that are managed by the sites themselves. A call to a write on a site is a cause of the publications of the next read on this site, so the write is a cause of all the consequences of the read. Moreover, preemption is figured by dotted arrows. The call to each() ? and all its consequences ? is preempted by the publication made by timer, 2000.

T. Andrews, F. Curbera, H. Dholakia, Y. Goland, J. Klein et al., Business Process Execution Language for Web Services. Version 1.1, 2003.

D. Kitchin, A. Quark, W. Cook, and J. Misra, The Orc Programming Language, Formal Techniques for Distributed Systems, pp.1-25, 2009.
DOI : 10.1007/11817949_32

D. Kitchin, W. Cook, and J. Misra, A Language for Task Orchestration and Its Semantic Properties, Lecture Notes in Computer Science, vol.4137, pp.477-491, 2006.
DOI : 10.1007/11817949_32

S. Rosario, A. Benveniste, S. Haar, and C. Jard, Foundations for Web Services Orchestrations: Functional and QoS Aspects, Jointly, Second International Symposium on Leveraging Applications of Formal Methods, Verification and Validation (isola 2006), pp.15-19, 2006.
DOI : 10.1109/ISoLA.2006.8

G. D. Plotkin, The Origins of Structural Operational Semantics, J. Log. Algebr . Program, vol.6061, pp.3-15, 2004.

L. Lamport, Time, clocks, and the ordering of events in a distributed system, Communications of the ACM, vol.21, issue.7, pp.558-565, 1978.
DOI : 10.1145/359545.359563

C. J. Fidge, Timestamps in message-passing systems that preserve the partial ordering, Proc. of the 11th Australian Computer Science Conference (ACSC'88), pp.56-66, 1988.

G. Ros¸uros¸u and K. Sen, An instrumentation technique for online analysis of multithreaded programs, of Concurrency and Computation: Practice and Experience, pp.311-325, 2007.

E. Giachino and I. Lanese, Causal-Consistent Reversible Debugging, Lecture Notes in Computer Science, vol.8411, pp.370-384, 2014.
DOI : 10.1007/978-3-642-54804-8_26
URL : https://hal.archives-ouvertes.fr/hal-01089270

M. Boreale and D. Sangiorgi, A fully abstract semantics for causality in the ??-calculus, Acta Informaticae, vol.35, issue.5, pp.353-400, 1998.
DOI : 10.1007/3-540-59042-0_77

S. Rosario, D. Kitchin, A. Benveniste, W. Cook, S. Haar et al., Event Structure Semantics of Orc, 4th International Workshop on Web Services and Formal Methods (WS-FM 2007), pp.154-168
DOI : 10.1007/978-3-540-79230-7_11
URL : https://hal.archives-ouvertes.fr/inria-00638299

R. Bruni, H. Melgratti, and E. Tuosto, Translating Orc Features into Petri Nets and the Join Calculus, 3rd International Workshop on Web Services and Formal Methods (WS-FM 2006), pp.123-137
DOI : 10.1007/11841197_8

J. Misra and W. Cook, Computation Orchestration, Software & Systems Modeling, vol.26, issue.6, pp.83-110, 2007.
DOI : 10.1007/s10270-006-0012-1

G. Winskel, Event structures Advances in Petri Nets, Springer Lecture Notes in Computer Science, vol.255, 1987.

M. Perrin, C. Jard, A. Mostéfaoui, L. , and U. De, Building a concurrent operational semantics for the ORC language, Nantes, 2014.