APA-referens (7:e uppl.)

Gopal, M. (1997). Digital control and state variable methods. Tata McGraw-Hill.

Chicago-referens (17:e uppl.)

Gopal, M. Digital Control and State Variable Methods. New Delhi: Tata McGraw-Hill, 1997.

MLA-referens (9:e uppl.)

Gopal, M. Digital Control and State Variable Methods. Tata McGraw-Hill, 1997.