Gaya APA
Lehnert, Josef. (1977).
Introduction to telegraph engineering (2nd ed.).
Berlin:
Siemens.
Gaya Chicago
Lehnert, Josef.
Introduction to telegraph engineering.
2nd ed.
Berlin:
Siemens,
1977.
Text.
Gaya MLA
Lehnert, Josef.
Introduction to telegraph engineering.
2nd ed.
Berlin:
Siemens,
1977.
Text.
Gaya Turabian
Lehnert, Josef.
Introduction to telegraph engineering.
2nd ed.
Berlin:
Siemens,
1977.
Print.