@conference{vlker1971the, title = {The Alteration of the Reverberation Times in a Small Theatre and a Concert Hall Using Loudspeaker Equipment}, author = {Völker, Ernst-Joachim}, booktitle = {Audio Engineering Society Convention 40}, month = {Apr}, year = {1971}, url = {https://www.aes.org/e-lib/browse.cfm?elib=1897} }