Circular imports? (newbie)

Although XMLSchema spec section 4.2.2 clearly states that it is invalid 
to import into a namespace a schema from the same namespace, it is not 
clearly spelled out that (whether?) it holds for descendant imports.

In particular we are trying to understand a schema presented us where a 
schema (A:parent) from namespace A imports a schema (B:child) from 
namespace B which, in turn, imports a schema (A:generation) from 
namespace A. It appears to me that these schema should not validate.

Reviewing the archives I see questions about circularity of schema but 
not quite this issue.

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