(a) Callouts. Callouts are used to describe various areas of a figure. Not all figures have callouts. They are set with runover indented 1 em. It is recommended that abbreviations be limited in callouts.
(b) Captions for Multiple Illustrations within a Figure. Some figures are composed of multiple illustrations. An illustration is identified by an illustration caption, which is boldface, uc/lc, and centered directly below the illustration. Letters (a), (b), (c), etc. are added to the beginning of each illustration caption to make in-text cross-referencing of figure illustrations possible [e.g., “see Fig. U-1, illustration (a)”]. Illustrations are set left to right (see Sample).
