cesEst: no visible global function definition for 'optim'
cesEst: no visible global function definition for 'nlm'
cesEst: no visible global function definition for 'nlminb'
cesEst: no visible global function definition for 'as.formula'
cesEst: no visible global function definition for 'nls'
cesEst: no visible global function definition for 'coef'
cesEst: no visible global function definition for 'deviance'
cesEstKmenta: no visible global function definition for 'formula'
cesEstKmenta: no visible global function definition for 'model.frame'
cesEstKmenta: no visible global function definition for 'coef'
cesEstKmenta: no visible global function definition for 'vcov'
plot.cesEst: no visible global function definition for 'par'
plot.cesEst: no visible global function definition for 'coef'
plot.cesEst: no visible global function definition for
  'colorRampPalette'
plot.cesEst: no visible binding for global variable 'persp'
plot.cesEst: no visible global function definition for 'plot.default'
plot.cesEst: no visible global function definition for 'points'
print.cesEst: no visible global function definition for 'coef'
print.summary.cesEst: no visible global function definition for 'coef'
print.summary.cesEst: no visible global function definition for
  'printCoefmat'
summary.cesEst: no visible global function definition for 'residuals'
summary.cesEst: no visible global function definition for 'fitted'
summary.cesEst: no visible global function definition for 'coef'
Undefined global functions or variables:
  as.formula coef colorRampPalette deviance fitted formula model.frame
  nlm nlminb nls optim par persp plot.default points printCoefmat
  residuals vcov
Consider adding
  importFrom("grDevices", "colorRampPalette")
  importFrom("graphics", "par", "persp", "plot.default", "points")
  importFrom("stats", "as.formula", "coef", "deviance", "fitted",
             "formula", "model.frame", "nlm", "nlminb", "nls", "optim",
             "printCoefmat", "residuals", "vcov")
to your NAMESPACE file.