Royce 1970's diagram 7 is a good one. It illustrates what we nowadays would call a prototype or spike solution 
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During the Preliminary Program Design phase, you develop what is "simply the entire process done in miniature, to a time scale that is relatively small with respect to the overall effort."
Double-click to expand.
It has two good examples of a Visual Chunk. The top diagonal is the now-familiar waterfall. The lower is the prototype.
I like how the lower chunk's phases are drawn overlapping rather than connected by arrows. This correctly alludes to the prototype's being the smaller effort (around 1/4 to 1/3 of the total). Contrast to Royce70 Diagram 5.
The arrows emitted from the prototype chunk nicely capture that the prototype influences all downstream phases.