L13_A
13-1   Definition of Fourier Series
13-2   The Effect of Symmetry
13-3a  Application in Circuit Analysis

L13_B
13-3b  Application in Circuit Analysis

L13_C
13-4   Average Power Calculations with Periodic Functions
13-5   The RMS Value of a Periodic Function

L13_D
13      Summary

L13_E
13      Summary