An Introduction to Statistical Learning: With Applications in R, Gareth James, Daniela Witten, Trevor Hastie, Rob Tibshirani, 2013 (Springer) - A foundational textbook explaining the statistical principles behind model evaluation, including the methodology of splitting data for robust assessment of generalization error.
sklearn.model_selection.train_test_split, scikit-learn developers, 2023 (scikit-learn) - The official documentation for the train_test_split function in scikit-learn, detailing its parameters, usage, and practical application for data partitioning.