To cite speckle in publications use:

  Belinda Phipson, Choon Boon Sim, Enzo R Porrello, Alex W Hewitt,
  Joseph Powell, Alicia Oshlack. propeller: testing for differences in
  cell type proportions in single cell data, Bioinformatics, Volume 38,
  Issue 20, 15 October 2022, Pages 4720–4726

A BibTeX entry for LaTeX users is

  @Article{,
    title = {propeller: testing for differences in cell type proportions in single cell data},
    author = {Belinda Phipson and Choon Boon Sim and Enzo R Porrello and Alex W Hewitt and Joseph Powell and Alicia Oshlack},
    journal = {Bioinformatics},
    year = {2022},
    volume = {38},
    number = {20},
    pages = {-6},
    url = {https://doi.org/10.1093/bioinformatics/btac582},
  }