Παραπομπή APA

Krog, D. R. (1984). The economics of terracing in Iowa. Ames: Center for Agricultural and Rural Development. Iowa State University.

Παραπομπή Chicago Style

Krog, David R. The Economics of Terracing in Iowa. Ames: Center for Agricultural and Rural Development. Iowa State University, 1984.

Παραπομπή MLA

Krog, David R. The Economics of Terracing in Iowa. Ames: Center for Agricultural and Rural Development. Iowa State University, 1984.

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