References: System Properties and Analysis

1. Linear time-invariant system - Wikipedia - Explains linearity, time invariance, impulse response, eigenfunctions, convolution, and frequency response for the central system class.

2. Causal system - Wikipedia - Defines causality for continuous- and discrete-time systems and relates output dependence to present and past inputs.

3. BIBO stability - Wikipedia - Presents bounded-input bounded-output stability criteria and their relationship to impulse responses and transfer functions.

4. Signals and Systems (2nd Edition) - Simon Haykin and Barry Van Veen - Wiley - Haykin’s integrated examples connect abstract system properties with communication, control, and filtering applications.

5. Structure and Interpretation of Signals and Systems - Edward A. Lee and Pravin Varaiya - Addison-Wesley - Lee and Varaiya’s executable-model approach clarifies composition, state, feedback, causality, and system behavior.

6. Signals and Systems Lecture Notes - MIT OpenCourseWare - Provides focused notes on feedback, poles, impulse response, frequency response, and continuous- and discrete-time systems.

7. Signals and Systems - Engineering LibreTexts - Develops LTI properties, differential and difference equations, stability, impulse response, and frequency-domain interpretations with examples.

8. SciPy Signal Processing - SciPy - Documents computational tools for impulse responses, frequency responses, filtering, convolution, and system representations used in practical analysis.

9. DSP 101 Part 1 - Analog Devices - Contrasts analog and digital systems while illustrating response, filter structure, implementation, and design tradeoffs.

10. The Scientist and Engineer's Guide to DSP - Steven W. Smith - Uses diagrams and practical examples to relate impulse, step, and frequency responses to linear system behavior.