Bard's Oath is the third in the Dragonlord series by Joanne Bertin and was published in 2012. It takes place in a world of truehumans, truedragons, and dragonlords - beings which have both human and dragon souls and can change from human to dragon and vice versa at will. It was preceded by the short story Dragonlord's Justice, The Last Dragonlord and Dragon and Phoenix. Source: Wikipedia (en)