Dyfyniad APA

National Geographic Society (United States). Cartographic Division, Doyle, R. E., Grosvenor, M. B., Grosvenor, G. M., Peele, W. T., & Cook, D. W. (1977). Europe [cartographic material]. The Society.

Dyfyniad Arddull Chicago

National Geographic Society (United States). Cartographic Division, Robert E. Doyle, Melville Bell Grosvenor, Gilbert M. Grosvenor, William T. Peele, and David W. Cook. Europe [cartographic Material]. Washington, D.C: The Society, 1977.

Dyfyniad MLA

National Geographic Society (United States). Cartographic Division, et al. Europe [cartographic Material]. The Society, 1977.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.