Dyfyniad APA

 Twidell, J. (2015).  Renewable energy resources.  Routledge, Taylor & Francis Group.

Dyfyniad Arddull Chicago

 Twidell, John.  Renewable Energy Resources.  Routledge, Taylor & Francis Group, 2015.

Dyfyniad MLA

 Twidell, John.  Renewable Energy Resources.  Routledge, Taylor & Francis Group, 2015.

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