Shepherd, W., & Shepherd, D. W. (2003). Energy studies (2nd ed.). Imperial College Press.
Dyfyniad Arddull ChicagoShepherd, W., and D. W. Shepherd. Energy Studies. 2nd ed. London [England]: Imperial College Press, 2003.
Dyfyniad MLAShepherd, W., and D. W. Shepherd. Energy Studies. 2nd ed. Imperial College Press, 2003.
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