Cita APA (7th ed.)

Zimbardo, P. G. (1989). Shyness: What it is. Addison-Wesley.

Cita Chicago (17th ed.)

Zimbardo, Philip G. Shyness: What It Is. Massachusetts: Addison-Wesley, 1989.

Cita MLA (9th ed.)

Zimbardo, Philip G. Shyness: What It Is. Addison-Wesley, 1989.