To cite package 'bvpSolve' in publications use:

  Francesca Mazzia, Jeff R. Cash, Karline Soetaert (2014).  Solving
  boundary value problems in the open source software R: Package
  bvpSolve.  Opuscula mathematica, 34(2), 387--403.
  https://www.opuscula.agh.edu.pl/vol34/2/art/opuscula_math_3424.pdf

A BibTeX entry for LaTeX users is

  @Article{,
    title = {Solving boundary value problems in the open source software R: Package bvpSolve},
    author = {{Francesca Mazzia} and {Jeff R. Cash} and {Karline Soetaert}},
    journal = {Opuscula mathematica},
    volume = {34},
    number = {2},
    pages = {387--403},
    year = {2014},
  }
