Dyfyniad APA

Cromley, E. K., & McLafferty, S. (2002). GIS and public health. Guilford Press.

Dyfyniad Arddull Chicago

Cromley, Ellen K., and Sara McLafferty. GIS and Public Health. New York: Guilford Press, 2002.

Dyfyniad MLA

Cromley, Ellen K., and Sara McLafferty. GIS and Public Health. Guilford Press, 2002.

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