Scientific opinion of the EFSA Panel on Plant Protection Products and their Residues on clustering and ranking of emissions of plant protection products from protecteds crops (greenhouses and crops grown under cover) to relevant environmental compar..., EFSA Panel on Plant Protection Products and their Residues(PPR), and Vleminckx Christiane , EFSA Journal, 21/3/2012, Volume 10, Issue 3, p.2611, (2012)