https://cran.r-universe.dev/modQRhttps://cran.r-universe.dev/api/packages/modQRhttps://cran.r-universe.dev/modQR/modQR.pdfhttps://cran.r-universe.dev/modQR/doc/manual.htmlhttps://cran.r-universe.dev/modQR/citationhttps://cran.r-universe.dev/modQR/citation.txthttps://cran.r-universe.dev/modQR/citation.cff