@CONFERENCE{kalis_viab_env,
    author = {Maciej Kalisiak and Michiel van de Panne},
    title = {Approximate Safety Enforcement Using Computed Viability Envelopes},
    journal = {IEEE Int. Conference on Robotics and Automation},
    year = {2004},
    volume = {5},
    pages = {4289--4294},
    otherinfo = {}
}