To cite Signac, please use:

  Stuart et al. Single-cell chromatin state analysis with Signac.
  Nature Methods (2021).

A BibTeX entry for LaTeX users is

  @Article{,
    author = {Tim Stuart and Avi Srivastava and Shaista Madad and Caleb Lareau and Rahul Satija},
    title = {Single-cell chromatin state analysis with Signac},
    journal = {Nature Methods},
    year = {2021},
    doi = {10.1038/s41592-021-01282-5},
    note = {https://doi.org/10.1038/s41592-021-01282-5},
  }