Time, Clocks, and the Ordering of Events in a Distributed System

@article{lamport-acmcomm21,
   address = {New York, NY, USA},
   apice = {LamportAcmcomm21},
   author = {Lamport, Leslie},
   doi = {10.1145/359545.359563},
   issn = {0001-0782},
   journal = {Communications of the ACM},
   number = 7,
   pages = {558--565},
   publisher = {ACM},
   title = {Time, Clocks, and the Ordering of Events in a Distributed System},
   url = {359563},
   volume = 21,
   year = 1978
}