@conference{dekoning1980sq6, title = {SQ6, A Functional Integrated PA Center}, author = {de Koning, S. H. and Smallenberg, W. A. L.}, booktitle = {Audio Engineering Society Convention 65}, month = {Feb}, year = {1980}, url = {https://www.aes.org/e-lib/browse.cfm?elib=3774} }