1. Directive 2002/96/EC of the European Parliament and of the Council of 27 January 2003 on waste electrical and electronic equipment (WEEE) - Joint declaration of the European Parliament, the Council and the Comission relating to Article 9. OJEU - L 2003, 37, 24-39.
2. United Nations, Resolution adopted by the General Assembly of the United Nations on 25th September 2015: Transforming our world: the 2030 Agenda for Sustainable Development. 2015, 77th General Assembly, 35.
3. Recent Developments and Future Perspectives of Lead-Free Ferroelectrics;Eichel;Funct. Mater. Lett.,2011
4. Perspective on the Development of Lead-free Piezoceramics;Rödel;J. Am. Ceram. Soc,2009
5. What Can Be Expected from Lead-Free Piezoelectric Materials?;Damjanovic;Funct. Mater. Lett,2011