1. Waclawsca I, Szumera M (2009) J Alloys Compd 468:246–253
2. Azooz MA, Abou Aiad THM, ElBatal FH, ElTabii G (2008) Indian J Pure Appl Phys 46:880–888
3. Monem AS, ElBatal HA, Khalil EMA, Azooz MA, Hamdy YM (2008) J Mater Sci Mater Med 19(3):1097–1108
4. Samuneva B, Bozadjor P, Djambaski P, Rangelova N (2000) Glass Technol 41:206–208
5. Samuneva B, Rangelova N, Bozadjor P, Djambaski P (2002) Glastech Ber Glass Sci Technol 75C2:233–238