https://swfsc.r-universe.dev/sprexhttps://swfsc.r-universe.dev/api/packages/sprexhttps://swfsc.r-universe.dev/sprex/sprex.pdfhttps://swfsc.r-universe.dev/sprex/doc/manual.htmlhttps://swfsc.r-universe.dev/sprex/citationhttps://swfsc.r-universe.dev/sprex/citation.txthttps://swfsc.r-universe.dev/sprex/citation.cff