Dyfyniad APA

Walker, M. P. (2018). Why we sleep: The new science of sleep and dreams. Penguin Books.

Dyfyniad Arddull Chicago

Walker, Matthew P. Why We Sleep: The New Science of Sleep and Dreams. UK: Penguin Books, 2018.

Dyfyniad MLA

Walker, Matthew P. Why We Sleep: The New Science of Sleep and Dreams. Penguin Books, 2018.

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