It appears you don't have a PDF plugin for this browser. You can click here to download the reference manual.
1.3.0 by Jose Barrera-Gomez, a year ago
https://sites.google.com/view/josebarrera/
Browse source code at https://github.com/cran/christmas
Authors: Jose Barrera-Gomez [aut, cre]
Documentation: PDF Manual
GPL-2 license
Imports animation, grDevices, graphics, stats, methods
Suggests testthat
See at CRAN