504 metalworking fluids. biodegradability. EcotoxicityGerulová, Kristína, 1980- Metalworking Fluids Biodegradability and Ecotoxicity Assessment. -- 1st ed. -- Dresden : IFW, 2012. -- 72 s. -- ISBN : 978-3-9808314-7-5. Piatrik, Milan. Černecký, Jozef. Polívka, Ľudevít