Dyfyniad APA
Ruhe, R. V. (1969). Quaternary landscapes in Iowa ([1st ed.].). Iowa State University Press.
Dyfyniad Arddull Chicago
Ruhe, Robert V. Quaternary Landscapes in Iowa. [1st ed.]. Ames: Iowa State University Press, 1969.
Dyfyniad MLA
Ruhe, Robert V. Quaternary Landscapes in Iowa. [1st ed.]. Iowa State University Press, 1969.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.