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Part 1 The head in general: the skull the features. Part 2 Muscles of expression: the nature of the facial muscles muscles of the brow and eye the muscles of the mouth. Part 3 The six expressions: the expression of sadness the expression of anger the expression of joy the expression of fear the expression of disgust the expression of surprise. Part 4 The complete guide to facial expression - a chart.
Faigin et al. (Thu,) studied this question.