This is my third full paper. My first publication (2009) is in Bahasa Malaysia, which was published as a chapter in book (to date I have not read it yet). It was a product of my final year project for B. Sc. My second paper (2010) was a product of 2 weeks work in West Java, Indonesia. The latest is my M. Sc. dissertation (2011). One publication per year, I hope I'll publish more in future.