@conference{herrera2004automatic, title = {Automatic Extraction of Tonal Metadata from Polyphonic Audio Recordings}, author = {Herrera, Perfecto}, booktitle = {Audio Engineering Society Conference: 25th International Conference: Metadata for Audio}, month = {Jun}, year = {2004}, url = {https://www.aes.org/e-lib/browse.cfm?elib=12805} }