Ogun State Governor, Senator Ibikunle Amosun, on Monday, joined other governors, serving and former Heads of States and several other dignitaries to celebrate President Muhammadu Buhari with the launch of a book titled, "Muhammadu Buhari: The Challenges of Leadership in Nigeria." The Ogun State Governor served as Chairman, Organising Committee for the launch of the book written by Professor John Paden.