Sisam, J. (1947). The use of aerial survey in forestry and agriculture (6th.). Imperial forestry bureau and pastures and field crops.
Chicago-viite (17. p.)Sisam, J.W.B. The Use of Aerial Survey in Forestry and Agriculture. 6th. Aberystwyth: Imperial forestry bureau and pastures and field crops, 1947.
MLA-viite (9. p.)Sisam, J.W.B. The Use of Aerial Survey in Forestry and Agriculture. 6th. Imperial forestry bureau and pastures and field crops, 1947.
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