To cite package ‘SigTree’ in publications use:

  Stevens J.R., Jones T.R., Lefevre M., Ganesan B., and Weimer B.C.
  (2017) SigTree: A Microbial Community Analysis Tool to Identify and
  Visualize Significantly Responsive Branches in a Phylogenetic Tree.
  Computational and Structural Biotechnology Journal 15:372-378.

A BibTeX entry for LaTeX users is

  @Article{,
    author = {John R. Stevens and Todd R. Jones and Michael Lefevre and Balasubramanian Ganesan and Bart C. Weimer},
    title = {SigTree: A Microbial Community Analysis Tool to Identify and Visualize Significantly Responsive Branches in a Phylogenetic Tree},
    journal = {Computational and Structural Biotechnology Journal 15:372-378},
    year = {2017},
  }