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Dyfyniad Arddull ChicagoArias, Priscila R. "Why Upland Farmers Adopt Conservation Measures." Manila Bulletin 1997.
Dyfyniad MLAArias, Priscila R. "Why Upland Farmers Adopt Conservation Measures." Manila Bulletin, 1997.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.