BARKER JOEL ARTHUR. (1993). PARADIGMS: THE BUSINESS OF DISCOVERING THE FUTURE. HARPER COLLINS PUBLISHERS.
Čikaški stil citiranja (17. izdanje)BARKER JOEL ARTHUR. PARADIGMS: THE BUSINESS OF DISCOVERING THE FUTURE. NEW YPRK: HARPER COLLINS PUBLISHERS, 1993.
MLA način citiranja (9. izdanje)BARKER JOEL ARTHUR. PARADIGMS: THE BUSINESS OF DISCOVERING THE FUTURE. HARPER COLLINS PUBLISHERS, 1993.
Upozorenje: Ovi citati možda nisu uvijek 100% točni.