transfer function - Consider an ideal low pass filter $H(\omega)$, and the input to this filter is the periodic square wave $x(t)$. Find the output $y(t)$ - Signal Processing Stack Exchange
Practical Introduction to Digital Filter Design - MATLAB & Simulink Example
5.1 Calculate the impulse response of an ideal low-pass filter. - YouTube
transfer function - Impulse response of IIR low-pass filter - Signal Processing Stack Exchange