Caron, J. P., Jamieson, D. G. & Dewar, R. E. (1980). Evaluating pictographs using semantic differential and classification techniques. Ergonomics, 23(2), 137-146.

Three experiments confirm the appropriateness of the semantic differential technique as a method for measuring the extent to which various public information pictographic signs convey their intended meaning. A general classification technique, which minimizes preliminary testing, was shown to be an efficient method for measuring the similarity of meaning of pictographs to their intended lettered translation. Application of this classification technique was illustrated by examining the contribution of components of the pictographic signs to the conveyed meaning.