Bagging predictors, Leo Breiman, 1996Machine Learning, Vol. 24 (Kluwer Academic Publishers)DOI: 10.1007/BF00058655 - Foundational paper introducing bootstrap aggregating (bagging) as an ensemble method, demonstrating its effectiveness in reducing variance and improving accuracy.
The Elements of Statistical Learning: Data Mining, Inference, and Prediction, Trevor Hastie, Robert Tibshirani, and Jerome Friedman, 2009 (Springer) - A comprehensive textbook providing a statistical perspective on ensemble methods, including discussions on bagging, boosting, and the bias-variance tradeoff.
Pattern Recognition and Machine Learning, Christopher M. Bishop, 2006 (Springer) - A classic textbook that provides a probabilistic and statistical treatment of machine learning, covering ensemble methods and their underlying principles.