https://valentint.r-universe.dev/splshttps://valentint.r-universe.dev/api/packages/splshttps://valentint.r-universe.dev/spls/spls.pdfhttps://valentint.r-universe.dev/spls/doc/manual.htmlhttps://valentint.r-universe.dev/spls/citationhttps://valentint.r-universe.dev/spls/citation.txthttps://valentint.r-universe.dev/spls/citation.cffhttps://valentint.r-universe.dev/spls/doc/spls-example.Rnwhttps://valentint.r-universe.dev/articles/spls/spls-example.pdf