APA

(19). Contributions to the data on theoretical metallurgy. Washington, DC: United States Gov. Print. Office.

Chicago

19. Contributions to the data on theoretical metallurgy. Washington, DC: United States Gov. Print. Office.

Harvard

(19). Contributions to the data on theoretical metallurgy. Washington, DC: United States Gov. Print. Office.

MLA

Contributions to the data on theoretical metallurgy. Washington, DC: United States Gov. Print. Office. 19.