To cite LMest in publications use:

Bartolucci F, Pandolfi S and Pennoni F (2017). “LMest: An R Package for Latent Markov Models for Longitudinal Categorical Data.” Journal of Statistical Software, 81(4), pp. 1–38. doi: 10.18637/jss.v081.i04.

Corresponding BibTeX entry:

  @Article{,
    title = {{LMest}: An {R} Package for Latent Markov Models for
      Longitudinal Categorical Data},
    author = {Francesco Bartolucci and Silvia Pandolfi and Fulvia
      Pennoni},
    journal = {Journal of Statistical Software},
    year = {2017},
    volume = {81},
    number = {4},
    pages = {1--38},
    doi = {10.18637/jss.v081.i04},
  }