@incollection{statemachine,
    author = {Fred Schneider},
    title = {Replication Management using the State Machine Approach},
    booktitle = {Distributed Systems (2nd edition)},
    publisher = {Addison-Wesley},
    note = {Chapter 7}, 
    editor = {Sape Mullender},
    year = {1993},
    pdfurl = {http://www.disi.unitn.it/~montreso/ds/syllabus/papers/StateMachine.pdf}
}