Freund, F. T. (2007). Pre-earthquake signals – Part I: Deviatoric stresses turn rocks into a source of electric currents. Copernicus Publications.
Čikaški stil citiranja (17. izdanje)Freund, F. T. Pre-earthquake Signals – Part I: Deviatoric Stresses Turn Rocks into a Source of Electric Currents. Copernicus Publications, 2007.
MLA način citiranja (9. izdanje)Freund, F. T. Pre-earthquake Signals – Part I: Deviatoric Stresses Turn Rocks into a Source of Electric Currents. Copernicus Publications, 2007.
Upozorenje: Ovi citati možda nisu uvijek 100% točni.