The list returned by the add.Reference()
function.
Plot
If set to TRUE, a sub-directory will be
created in the working directory. This sub-directory will
contains png plots describing the validation analysis.
Color
The color that will be used for the plots
(HTML notation).
Excel
If set to TRUE, a sub-directory will be
created in the working directory. This sub-directory will
contains excel files describing the validation analysis.