@article{jflp97-06,
      author={Enea Zaffanella, Roberto Giacobazzi, and Giorgio Levi},
      title={Abstracting Synchronization in Concurrent Constraint Programming},
      journal={Journal of Functional and Logic Programming},
      volume={1997},
      number={6},
      publisher={The MIT Press},
      month={November},
      year={1997}
    }