info:oai:orgprints.org:4364info:ofi/fmt:xml:xsd:bookHalbergNielsHalberg, NielsDalgaardR.Dalgaard, R.BerntsenJ.Berntsen, J.OlesenJ.E.Olesen, J.E.DalgaardT.Dalgaard, T.2005Organic cash crop farms as net energy producers: Energy balances and environmental effectsproceeding