Package check result: NOTE

Check: CRAN incoming feasibility, Result: NOTE
  Maintainer: ‘Jeffrey S. Racine <racinej@mcmaster.ca>’
  
  Found the following (possibly) invalid URLs:
    URL: https://github.com/JeffreyRacine/R-Package-np/tarball/master
      From: README.md
      Status: 404
      Message: Not Found
    URL: https://github.com/JeffreyRacine/R-Package-np/zipball/master
      From: README.md
      Status: 404
      Message: Not Found