for non-standard things in the check directory

Maintainer: ‘J Andres Christen <jac@cimat.mx>’

No Authors@R field in DESCRIPTION.
Please add one, modifying
  Authors@R: person(given = c("J", "Andres"),
                    family = "Christen",
                    role = c("aut", "cre"),
                    email = "jac@cimat.mx")
as necessary.

Problems when reading CITATION file:
  It is recommended to use ‘given’ instead of ‘middle’.
Found the following files/directories:
  ‘Tsttwalk.dat’
Maintainer: ‘J Andres Christen <jac@cimat.mx>’

No Authors@R field in DESCRIPTION.
Please add one, modifying
  Authors@R: person(given = c("J", "Andres"),
                    family = "Christen",
                    role = c("aut", "cre"),
                    email = "jac@cimat.mx")
as necessary.

Problems when reading CITATION file:
  It is recommended to use ‘given’ instead of ‘middle’.
Found the following files/directories:
  ‘Tsttwalk.dat’
Found the following files/directories:
  ‘Tsttwalk.dat’
Found the following files/directories:
  ‘Tsttwalk.dat’
Found the following files/directories:
  ‘Tsttwalk.dat’
Found the following files/directories:
  ‘Tsttwalk.dat’