More specifically, in the following script, three sinusoidal signals (tones) of different frequencies are synthetically generated and their sum is computed and plotted. The resulting signal is, therefore, a sum of tones and the tone of maximum frequency (900 Hz) determines the Nyquist rate. Therefore, in this case, a sampling frequency of at least 1800 Hz is required.
Epri (2019). A Synthetic Sound (https://www.mathworks.com/matlabcentral/fileexchange/70251-a-synthetic-sound), MATLAB Central File Exchange. Retrieved .
Introduction to Audio Analysis, by THEODOROS GIANNAKOPOULOS AGGELOS PIKRAKIS, 2014