Several authors have described wide variations in the number of night visits, which have proved difficult to explain.

The cycle types article describes additional variations.

Mr. Krulwich entertainingly describes several variations on this basic plot.

The term was originally used to describe variations in chemical structure.

Those studies, while describing variations in organisms, may have contained descriptions of at least two species, she said.

Later patents describe further variations of packets with variable length.

Roy also describes regional, ethnic and sectarian variations in mujahideen organization.

A framework for describing variations in state early intervention systems.

It is not enough for grammars to describe variations in classes or structures.

Symbiosis, parasitism and all the rest are just ways of describing variations of the same basic process of living together.