SYDNEY, June 3: Mandawuy Yunupingu, lead singer of Australian rock band Yothu Yindi, which mixed traditional Aboriginal music and modern rock, has died at the age of 56 after battling kidney disease. Best known for their 1991 hit “Treaty”, Yothu Yindi were strong advocates of reconciliation between white and Aboriginal Australians and helped put the issue on Australia’s national stage. The album “Tribal Voice” hit number three on the Billboard top world music albums chart in 1992. (agencies)