Cita APA (7a ed.)

Lehnert, J. (1977). Introduction to telegraph engineering (2nd ed.). Siemens-Heyden.

Cita Chicago Style (17a ed.)

Lehnert, Josef. Introduction to Telegraph Engineering. 2nd ed. Berlín-London: Siemens-Heyden, 1977.

Cita MLA (8a ed.)

Lehnert, Josef. Introduction to Telegraph Engineering. 2nd ed. Siemens-Heyden, 1977.