Drupal-Bibcite31<style face="normal" font="default" size="100%">The combination of DPP-4 inhibitors versus sulfonylureas with metformin after failure of first-line treatment in the risk for major cardiovascular events and death</style><style face="normal" font="default" size="100%">The combination of DPP-4 inhibitors versus sulfonylureas with metformin after failure of first-line treatment in the risk for major cardiovascular events and death</style>