Improving Transformer with an Admixture of Attention Heads - Nguyen, Tan; Nguyen, Tam; Do, Hai; Nguyen, Khai; Saragadam, Vishwanath; Pham, Minh; Nguyen, Khuong Duy; Ho, Nhat; Osher, Stanley (Advances in Neural Information Processing Systems, 2022)