Rights:
© 2013 American Physical Society (APS). This is the accepted version of the following article: Wu, Lu-Lu & Zhou, Hai-Jun & Alava, Mikko J. & Aurell, Erik & Orponen, Pekka. 2013. Witness of unsatisfiability for a random 3-satisfiability formula. Physical Review E. Volume 87, Issue 5. 052807/1-10. ISSN 1539-3755 (printed). DOI: 10.1103/physreve.87.052807, which has been published in final form at http://journals.aps.org/pre/abstract/10.1103/PhysRevE.87.052807.