1. Fresh produce consumption, 2002; www.pma.com/ii/mem_only/consumstats.pdf.
2. Healthy food for Europe's citizens. The European Union and food quality 2000;http://europa.eu.int/comm/dg10/publications/brochares/move/econo/food/txt_en.pdf.
3. U.S. Broccoli, 2000;http://nfapp.east.asu.edu/Outlook02/broccoli. htm.