Readers Digest Asso. (1980). Natural wonders of the world. RDA.
Chicagoスタイル(17版)引用形式Readers Digest Asso. Natural Wonders of the World. New York: RDA, 1980.
MLA(9版)引用形式Readers Digest Asso. Natural Wonders of the World. RDA, 1980.
警告: この引用は必ずしも正確ではありません.