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https://arxiv.org/abs/1810.04805
https://github.com/google-research/bert
https://en.wikipedia.org/wiki/BERT_(language_model)
https://ai.googleblog.com/2019/12/albert-lite-bert-for-self-supervised.html
https://arxiv.org/abs/1909.11942
https://github.com/google-research/ALBERT
https://arxiv.org/abs/1907.11692
https://github.com/google-research/text-to-text-transfer-transformer
https://github.com/google-research/t5x
https://arxiv.org/abs/1910.05276
http://exbert.net/
https://github.com/google-research/language
https://pytorch.org/tutorials/intermediate/dynamic_quantization_bert_tutorial.html
https://github.com/codertimo/BERT-pytorch
https://ai.googleblog.com/2017/08/transformer-novel-neural-network.html
https://ai.googleblog.com/2020/01/encode-tag-and-realize-controllable-and.html
https://ai.googleblog.com/2020/01/reformer-efficient-transformer.html