To cite package 'deSolve' in publications use:

Soetaert K, Petzoldt T, Setzer RW (2010). “Solving Differential Equations in R: Package deSolve.” Journal of Statistical Software, 33(9), 1–25. doi:10.18637/jss.v033.i09.

Corresponding BibTeX entry:

  @Article{,
    title = {Solving Differential Equations in {R}: Package de{S}olve},
    author = {Karline Soetaert and Thomas Petzoldt and R. Woodrow
      Setzer},
    journal = {Journal of Statistical Software},
    volume = {33},
    number = {9},
    pages = {1--25},
    year = {2010},
    doi = {10.18637/jss.v033.i09},
    keywords = {ordinary differential equations, partial differential
      equations, differential algebraic equations, initial value
      problems, R, FORTRAN, C},
  }