^John E. Hopcroft (2012). 9780201441246, Addison–Wesley. ISBN 9780201441246 (revised Nov 2013)
^Rajeev Motwani, Jeffrey D. Ullman, John E. HopcroftIntroduction to Automata Theory, Languages, and Computation by Rajeev Motwani, Jeffrey D. Ullman and John E. Hopcroft (2000, Hardcover, Revised)ISBN 9780201441246 (revised Dec 2014)