@misc {IOPORT.70559909,
    author       = {Broy, Manfred and Wirsing, Martin},
    title        = {On the algebraic specification of nondeterministic programming languages},
    howpublished = {CAAP, 162-179 (1981).},
    year         = {1981},
    doi          = {10.1007/3-540-10828-9_61},
    identifier   = {70559909},
}