The package source code is licensed under GPL-2 as stated in DESCRIPTION.

The file extdata/wine.data is the Wine dataset by Stefan Aeberhard and
M. Forina (1992), distributed by the UCI Machine Learning Repository under
the Creative Commons Attribution 4.0 International license (CC BY 4.0).

Source: https://archive.ics.uci.edu/dataset/109/wine
DOI: 10.24432/C5PC7J
License: https://creativecommons.org/licenses/by/4.0/