Found the following (possibly) invalid URLs:
  URL: ../doc/codebook.html
    From: man/codebook.Rd
  URL: ../doc/plots.html
    From: man/plot_design.Rd
  URL: ../doc/rnorm_multi.html
    From: man/rnorm_multi.Rd
  URL: ../doc/sim_df.html
    From: man/sim_df.Rd
  URL: ../doc/sim_mixed.html
    From: man/sim_mixed_cc.Rd
Found the following (possibly) invalid URLs:
  URL: ../doc/codebook.html
    From: man/codebook.Rd
  URL: ../doc/plots.html
    From: man/plot_design.Rd
  URL: ../doc/rnorm_multi.html
    From: man/rnorm_multi.Rd
  URL: ../doc/sim_df.html
    From: man/sim_df.Rd
  URL: ../doc/sim_mixed.html
    From: man/sim_mixed_cc.Rd