Lessons in Vocal Expression; Course I: Processes of Thinking in the Modulation of the Voice. E-book. Formato PDF S. S. Curry   -  Forgotten Books, 2017  - 

The word Expression covers every possible revelation of a human being, and implies any means or mode of manifesting the conceptions or emotions, the conditions or dispositions of the soul. Every art is an art of expression. Expression also names the manifestation in animals of their instinctive actions and conditions.