The Elements of Statistical Learning: Data Mining, Inference, and Prediction, Trevor Hastie, Robert Tibshirani, and Jerome Friedman, 2009 (Springer) - Provides a comprehensive statistical treatment of classification algorithms, including detailed explanations of decision boundaries for various models like logistic regression.
Hands-On Machine Learning with Scikit-Learn, Keras, and TensorFlow, Aurélien Géron, 2022 (O'Reilly Media, Inc.) - Offers practical examples and clear explanations of decision boundaries for various classification algorithms, including logistic regression, suitable for beginners.
CS229 Lecture Notes: Supervised Learning, Andrew Ng, Tengyu Ma, 2023 (Stanford University) - Covers logistic regression and the concept of decision boundaries from a foundational machine learning perspective, highly regarded.