Food and Agriculture Organisation of the United Nations Rome — December 1989. http://www.fao.org/ag/AGP/AGPP/Pesticid/Code/Download/ENVICRI.pdf
Food and Agriculture Organization of the United Nations Rome – Detsember 1989. http://www.fao.org/ag/AGP/AGPP/Pesticid/Code/Download/ENVICRI.pdf