Friddell, C., & Baddeley, E. (2021). Grace Banker and her Hello Girls answer the call: The heroic story of WWI telephone operators (First edition.). Calkins Creek, an imprint of Boyds Mills & Kane.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Friddell, Claudia, و Elizabeth Baddeley. Grace Banker and Her Hello Girls Answer the Call: The Heroic Story of WWI Telephone Operators. First edition. New York: Calkins Creek, an imprint of Boyds Mills & Kane, 2021.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Friddell, Claudia, و Elizabeth Baddeley. Grace Banker and Her Hello Girls Answer the Call: The Heroic Story of WWI Telephone Operators. First edition. Calkins Creek, an imprint of Boyds Mills & Kane, 2021.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.