@article{oai:nagoya.repo.nii.ac.jp:00031353,
 author = {Matsuura, Koji and Kawai, Junji},
 journal = {Memoirs of the Faculty of Engineering, Nagoya University},
 month = {Jan},
 note = {The authors pose here the problem of loudness in connection with other fundamental qualities of vowels, for example, with articulation quality which is almost independent of the influence caused by forte-piano difference in vocal intensity. One of the main characteristics of loudness is: when vowel patterns are cut down successively by Low-Cut Distortions, the difference of loudness due to vocal-intensity difference is quite conspicuous; meanwhile, when patterns are cut down by successive High-Cut Distortions, the difference of loudness caused by the same difference in vocal intensity is not noticeable. In this respect, the nature of loudness distribution in the frequency domain is exactly opposed to that of naturalness quality.},
 pages = {110--116},
 title = {Study on distribution characteristics of loudness quality of sustained vowels under the conditions of vocal intensity, piano and forte},
 volume = {15},
 year = {1964}
}