https://luislaum.r-universe.dev/grechttps://luislaum.r-universe.dev/api/packages/grechttps://luislaum.r-universe.dev/grec/grec.pdfhttps://luislaum.r-universe.dev/grec/doc/manual.htmlhttps://luislaum.r-universe.dev/grec/NEWShttps://luislaum.r-universe.dev/grec/NEWS.txthttps://luislaum.r-universe.dev/grec/citationhttps://luislaum.r-universe.dev/grec/citation.txthttps://luislaum.r-universe.dev/grec/citation.cff