@article{BroersenJAL2004,
    author = {J.M. Broersen},
    title = {Action negation and alternative reductions for dynamic deontic logics},
    journal = {Journal of Applied Logic},
    volume = {2},
    number = {1},
    publisher = {Elsevier},
    annote = {},
    pages = {153--168},
    year = {2004},
    note = {doi:10.1016/j.jal.2004.01.007}
    }