Journal of Automata, Languages and Combinatorics

@article{jalc160103,
  author  = {Michael Soltys},
  title   = {Feasible Proofs of Szpilrajn's Theorem -- A Proof-Complexity Framework for Concurrent Automata},
  journal = jalc,
  year    = 2011,
  volume  = 16,
  number  = {1},
  pages   = {27--38}
}