Rahmi M. Koç lets one work freely and as one pleases. I experienced this liberty while working on this book; I was to work as I wished and I was to receive his support on whatever subject, whenever I needed it. Ömer Koç almost competed with Rahmi M. Koç in helping me. Every once in while, I received a book, an article or a photograph to be used as a source from either one of them. This continued as such in all the stages of the project. Some of my foreign friends commented on the joy I displayed about working on this book. I apparently reflected my joy without realizing it.