Crystallography Online: the website of the International Union of Crystallography

>      "Note that reserved prefixes may not themselves contain underscore
>       characters."

I see no reason this should not be included in the specifications.

Brian (T.)

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Brian H. Toby, Ph.D.                    Leader, Crystallography Team
Brian.Toby at NIST.gov      NIST Center for Neutron Research, Stop 8562
voice: 301-975-4297     National Institute of Standards & Technology
FAX: 301-921-9847                        Gaithersburg, MD 20899-8562
                http://www.ncnr.nist.gov/xtal
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