Reference:
  Author: Ali José Mashtizadeh and Andrea Bittau and Yifeng Frang Huang and David Mazières
  Title: "Replication, History, and Grafting in the Ori File System"
  Journal: Proceedings of the Twenty-Fourth ACM Symposium on Operating Systems Principles
  Year: 2013
  Pages: 151-166
  DOI: http://dx.doi.org/10.1145/2517349.2522721
  URL: http://dl.acm.org/citation.cfm?id=2522721
  eprint: http://dl.acm.org/ft_gateway.cfm?id=2522721&ftid=1403940&dwn=1
