This certificate of publication is for an article titled "Microstructure and Mechanical Properties of Alumina-6061 Aluminum Alloy Joined by Friction Welding". The authors are M.N. Ahmad Fauzi, M.B. Uday, H. Zuhailawati, A.B. Ismail. The article was published in Materials & Design, Volume 31, Issue 2 in 2010 on pages 670-676.