@article{globalconvergenceofadaptivegradient,
  title = {Global Convergence of Adaptive Gradient Methods for An Over-parameterized Neural Network},
  author = {Xiaoxia Wu and Simon S. Du and Rachel Ward},
  year = {2019},
  eprint = {1902.07111},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/1902.07111v2},
}