@article{borys1980on, title = {On Intermodulation and Harmonic Distortion in Single-Amplifier Active Filters}, author = {Borys, Andrzej}, journal = {J. Audio Eng. Soc}, volume = {28}, number = {10}, pages = {706--712}, year = {1980}, url = {https://www.aes.org/e-lib/browse.cfm?elib=3956} }