A photo with my dear friend Mohammad Ridwan Agustiawan, after the successful defense of his master thesis. I will not say he was my student or I was his advisor/supervisor, cause I don't believe in vertical relationships in learning. He is just a great friend of mine. I enjoyed the long discussions we had together when he was working on his master thesis and I learned much from him. I also used to spend a good time with him playing soccer with other friends and colleagues. Mohammad Ridwan will start on April 1st at Vienna University of Technology as a research assistant and PhD student, and I'm very happy for him.