https://dmurdoch.r-universe.dev/polycorhttps://dmurdoch.r-universe.dev/api/packages/polycorhttps://dmurdoch.r-universe.dev/polycor/polycor.pdfhttps://dmurdoch.r-universe.dev/polycor/doc/manual.htmlhttps://dmurdoch.r-universe.dev/polycor/NEWShttps://dmurdoch.r-universe.dev/polycor/NEWS.txthttps://dmurdoch.r-universe.dev/polycor/citationhttps://dmurdoch.r-universe.dev/polycor/citation.txthttps://dmurdoch.r-universe.dev/polycor/citation.cff