@article{small1986total, title = {Total Difference-Frequency Distortion: Practical Measurements}, author = {Small, Richard H.}, journal = {J. Audio Eng. Soc}, volume = {34}, number = {6}, pages = {427--436}, year = {1986}, url = {https://www.aes.org/e-lib/browse.cfm?elib=5266} }