Brown, H. S. (1954). The challenge of man's future: An inquiry concerning the condition of man during the years that lie ahead. Viking Press.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Brown, Harrison Scott. The Challenge of Man's Future: An Inquiry Concerning the Condition of Man During the Years That Lie Ahead. New York: Viking Press, 1954.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Brown, Harrison Scott. The Challenge of Man's Future: An Inquiry Concerning the Condition of Man During the Years That Lie Ahead. Viking Press, 1954.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.