https://r-forge.r-universe.dev/pems.utilshttps://r-forge.r-universe.dev/api/packages/pems.utilshttps://r-forge.r-universe.dev/pems.utils/pems.utils.pdfhttps://r-forge.r-universe.dev/pems.utils/doc/manual.htmlhttps://r-forge.r-universe.dev/pems.utils/NEWShttps://r-forge.r-universe.dev/pems.utils/NEWS.txthttps://r-forge.r-universe.dev/pems.utils/citationhttps://r-forge.r-universe.dev/pems.utils/citation.txthttps://r-forge.r-universe.dev/pems.utils/citation.cff