Bihar Chief Minister and JD(U) President Nitish Kumar has called for maximum unity among the opposition ranks. He said, opposition's voice should be respected. He was speaking at a book release function in New Delhi. <br/><br/>The book titled Fearless Opposition- Power and Accountability has been written by Congress leader and former Union Minister P Chidambaram. On demonetisation, Mr Kumar said, the Centre should come out with details of black money detected post- demonetisation as well how much currency came into the banking system. <br/><br/>Mr Kumar appreciated Mr Chidambaram for writing on various issues including social and political. On the occasion, former Prime Minister Dr Manmohan Singh, Congress Vice President Rahul Gandhi, CPI(M) General Secretary Sitaram Yechury and Congress leader Kapil Sibal were present.