@article{hddl21towardsdefininganhtnformalism,
  title = {HDDL 2.1: Towards Defining an HTN Formalism with Time},
  author = {D. Pellier and H. Fiorino and M. Grand and A. Albore and R. Bailon-Ruiz},
  year = {2022},
  eprint = {2206.01822},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2206.01822v1},
}