@misc {IOPORT.20000033,
    author       = {Luttik, Bas and Valencia, Frank},
    title        = {Proceedings 18th international workshop on expressiveness in concurrency},
    howpublished = {EPTCS: EXPRESS 64 (2011).},
    year         = {2011},
    doi          = {10.4204/EPTCS.64},
    identifier   = {20000033},
}