Παραπομπή APA

Lessenberry, D., & Crawford, T. J. (1947). Twentieth century typewriting.

Παραπομπή Chicago Style

Lessenberry, Ddand, και T. James Crawford. Twentieth Century Typewriting. Ed5, 1947.

Παραπομπή MLA

Lessenberry, Ddand, και T. James Crawford. Twentieth Century Typewriting. 1947.