Emeritus Prof. Efstratios Theodossiou University of Athens, Department of Physics Pamepistimioupolis, Athens 15771, Greece Tel: 210 0363 5701 mob.: 693 7407614 e-mail: etheodos@phys.uoa.gr and eef.athens@gmail.com Web Site: http://www.stratos-theodosiou.gr/andhttps://eef.gr