Document Level Hierarchical Transformer Najam Zaidi author Trevor Cohn author Gholamreza Haffari author 2021-12 text Proceedings of the 19th Annual Workshop of the Australasian Language Technology Association Afshin Rahimi editor William Lane editor Guido Zuccon editor Australasian Language Technology Association Online conference publication zaidi-etal-2021-document https://aclanthology.org/2021.alta-1.13/ 2021-12 128 137