<http://schema.org/description>
"Mechanical interactions can have negative effects that may not seem obvious when discrete elements are being designed for assemblies. One software company has the means by which these subtractive characteristics can be eliminated before physical models are produced."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.autofieldguide.com/articles/when-the-whole-is-less-than-the-sum-of-the-parts(2)>