Clear. Consistent. Correct.
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Excel Style Guide

The Spreadsheet Style Manual
The Spreadsheet Style Manual
David Harrison and John Yu, 1990
 
Recent high profile blunders with spreadsheet analysis make it clear that spreadsheet authors need to realize that a spreadsheet is a program. There are better and worse ways to write them.
Unfortunately there is no recent book to recommend. Perhaps this is part of the problem.
"The authors provide a sound methodology for the development of clear and controlled spreadsheet applicationa."

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