To cite metaLik in publications use:

Annamaria Guolo, Cristiano Varin (2012). The R Package metaLik for Likelihood Inference in Meta-Analysis. Journal of Statistical Software, 50(7), 1-14. URL http://www.jstatsoft.org/v50/i07/.
Guolo, A. (2012). Higher-order likelihood inference in meta-analysis and meta-regression. Statistics in Medicine 31, 313-327.

Corresponding BibTeX entries:

  @Article{,
    title = {The {R} Package {metaLik} for Likelihood Inference in
      Meta-Analysis},
    author = {Annamaria Guolo and Cristiano Varin},
    journal = {Journal of Statistical Software},
    year = {2012},
    volume = {50},
    number = {7},
    pages = {1--14},
    url = {http://www.jstatsoft.org/v50/i07/},
  }
  @Article{,
    title = {Higher-order likelihood inference in meta-analysis and
      meta-regression},
    author = {Annamaria Guolo},
    year = {2012},
    journal = {Statistics in Medicine},
    number = {31},
    pages = {313--327},
  }