Gutfeld, G. (2020). The plus: Self-help for people who hate self-help (First Threshold Editions hardcover edition.). Threshold Editions.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Gutfeld, Greg. The Plus: Self-help for People Who Hate Self-help. First Threshold Editions hardcover edition. New York: Threshold Editions, 2020.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Gutfeld, Greg. The Plus: Self-help for People Who Hate Self-help. First Threshold Editions hardcover edition. Threshold Editions, 2020.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.