https://trinker.r-universe.dev/qdaphttps://trinker.r-universe.dev/api/packages/qdaphttps://trinker.r-universe.dev/qdap/qdap.pdfhttps://trinker.r-universe.dev/qdap/doc/manual.htmlhttps://trinker.r-universe.dev/qdap/NEWShttps://trinker.r-universe.dev/qdap/NEWS.txthttps://trinker.r-universe.dev/qdap/citationhttps://trinker.r-universe.dev/qdap/citation.txthttps://trinker.r-universe.dev/qdap/citation.cff