How in XML-schema do you make sure that of two possible child elements, either or both, but not neither are present?

Parent A

Parent B

Parent A B

should all be ok, but not Parent without either A or B. Attached is a small ZIP file with example files.

Paris was a good meeting, I am working on the minutes!

Thanks!

Gregor ---------------------------------------------------------- Gregor Hagedorn (G.Hagedorn@bba.de) Institute for Plant Virology, Microbiology, and Biosafety Federal Research Center for Agriculture and Forestry (BBA) Koenigin-Luise-Str. 19 Tel: +49-30-8304-2220 14195 Berlin, Germany Fax: +49-30-8304-2203

Often wrong but never in doubt!

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---- File information ----------- File: ParentChildABProblem.zip Date: 22 Feb 2003, 18:37 Size: 1639 bytes. Type: ZIP-archive