APA (7th ed.) Citation

Helbing, A. T. (1931). The departments of the American federation of labor. The John Hopkins press.

Chicago Style (17th ed.) Citation

Helbing, Albert Theodore. The Departments of the American Federation of Labor. Baltimore: The John Hopkins press, 1931.

MLA (9th ed.) Citation

Helbing, Albert Theodore. The Departments of the American Federation of Labor. The John Hopkins press, 1931.