APA
Williams E. H., . (2005). The nature handbook : a guide to observing the great outdoors. Oxford: Oxford University Press.
Chicago
Williams Ernest H, . 2005. The nature handbook : a guide to observing the great outdoors. Oxford: Oxford University Press.
Harvard
Williams E. H., . (2005). The nature handbook : a guide to observing the great outdoors. Oxford: Oxford University Press.
MLA
Williams Ernest H, . The nature handbook : a guide to observing the great outdoors. Oxford: Oxford University Press. 2005.