2 citations in nlme package

[certara-mtomashevskiy]

default print=TRUE argument for method.B causes a warning

In charToRaw(res.str) : argument should be a character vector of length 1
all but the first element will be ignored

the issue is in

> citation("nlme")
To cite package ‘nlme’ in publications use:

  Pinheiro J, Bates D, R Core Team (2023). _nlme: Linear and Nonlinear Mixed Effects Models_. R package version
  3.1-162, <https://CRAN.R-project.org/package=nlme>.

  Pinheiro JC, Bates DM (2000). _Mixed-Effects Models in S and S-PLUS_. Springer, New York. doi:10.1007/b98882
  <https://doi.org/10.1007/b98882>.

To see these entries in BibTeX format, use 'print(<citation>, bibtex=TRUE)', 'toBibtex(.)', or set
'options(citation.bibtex.max=999)'.

so they added another citation for the package.
I guess the best way would be to use

  cit <- citation("nlme")
  year3 <- paste0(" (", substr(cit, regexpr("year", cit) + 
    8, regexpr("year", cit) + 11), ")")**[1]**