To cite package 'solaR' in publications use:

Oscar Perpinan (2-03). solaR: Calculation of Solar Radiation and PV Systems. R package version 0.32.

Corresponding BibTeX entry:

  @Manual{,
    title = {solaR: Calculation of Solar Radiation and PV Systems.},
    author = {Oscar Perpinan},
    year = {2-03},
    note = {R package version 0.32},
  }