Correspondence

Prof. Dr. Şakir Ayık
Department of Physics
Tennessee Technological University
Cookville, USA

E-mail : ayik@tntech.edu
Phone : +1  (931) 372-3156
Fax     : +1  (931) 372-6351

 Prof. Dr. Ahmet Gökalp
Department of Physics
Middle East Technical University
06531 Ankara / Turkey

E-mail : agokalp@metu.edu.tr
Phone : +90 (312) 2103266
Fax     : +90 (312) 2101281		 Prof. Dr. Osman Yılmaz
Department of Physics
Middle East Technical University
06531 Ankara / Turkey

E-mail : oyilmaz@metu.edu.tr
Phone : +90 (312) 2105081
Fax     : +90 (312) 2101281