توثيق جمعية علم النفس الأمريكية APA (الطبعة السابعة)

Truesdell, L. E. (1965). The development of punch card tabulation in the Bureau of the Census, 1890-1940, with outlines of actual tabulation programs/ Leon Edgar Truesdell. U.S. Dept. of Commerce.

توثيق أسلوب شيكاغو (الطبعة السابعة عشر)

Truesdell, Leon Edgar. The Development of Punch Card Tabulation in the Bureau of the Census, 1890-1940, with Outlines of Actual Tabulation Programs/ Leon Edgar Truesdell. Washington: U.S. Dept. of Commerce, 1965.

توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)

Truesdell, Leon Edgar. The Development of Punch Card Tabulation in the Bureau of the Census, 1890-1940, with Outlines of Actual Tabulation Programs/ Leon Edgar Truesdell. U.S. Dept. of Commerce, 1965.