Cita APA (7th ed.)

Kaku Michio. (2006). Parallel Worlds. Penguin Books.

Cita Chicago (17th ed.)

Kaku Michio. Parallel Worlds. london: Penguin Books, 2006.

Cita MLA (9th ed.)

Kaku Michio. Parallel Worlds. Penguin Books, 2006.