To cite fxTWAPLS in publications use:

  Liu Mengmeng, Prentice Iain Colin, ter Braak Cajo J. F., Harrison
  Sandy P.. 2020 An improved statistical approach for reconstructing
  past climates from biotic assemblages. Proc. R. Soc. A. 476:
  20200346.  https://doi.org/10.1098/rspa.2020.0346

A BibTeX entry for LaTeX users is

  @Article{,
    title = {An improved statistical approach for reconstructing past climates from biotic assemblages},
    author = {Mengmeng Liu and Iain Colin Prentice and Cajo J. F. ter Braak and Sandy P. Harrison},
    journal = {Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences},
    year = {2020},
    volume = {476},
    url = {https://doi.org/10.1098/rspa.2020.0346},
  }