Supra-Textual Design: The Visual Rhetoric of Whole Documents
http://www.leaonline.com/doi/abs/10.1207/s15427625tcq0501_2
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  peer-reviewed

Kostelnick, Charles
Technical Communication Quarterly
1996

Abstract:

Supra-textual design encompasses the global visual language of a document and operates in three modes: textual, spatial, and graphic. The rhetoric of supra-textual design includes structural functions that provide global organization and cohesion and stylistic functions that affect credibility, tone, emphasis, interest, and usability. Supra-textual rhetoric extends to other documents through conventional codes and through sets and series. Because writers may not control the end product of supra-textual design, intention may also be a rhetorical factor.