https://aalfons.r-universe.dev/r2spsshttps://aalfons.r-universe.dev/api/packages/r2spsshttps://aalfons.r-universe.dev/r2spss/r2spss.pdfhttps://aalfons.r-universe.dev/r2spss/doc/manual.htmlhttps://aalfons.r-universe.dev/r2spss/NEWShttps://aalfons.r-universe.dev/r2spss/NEWS.txthttps://aalfons.r-universe.dev/r2spss/citationhttps://aalfons.r-universe.dev/r2spss/citation.txthttps://aalfons.r-universe.dev/r2spss/citation.cffhttps://aalfons.r-universe.dev/r2spss/doc/r2spss-intro.Rnwhttps://aalfons.r-universe.dev/articles/r2spss/r2spss-intro.pdf