Dear Hal and others,

Uwe Hortsmann and Willi Brand provided you already with the most
important references for the Cr-reduction method.
There are a few more refs I like to give you (and other interested
analysts) for completeness:

Rolle, W., F. Bigl, G. Haase, A. Runge, and H. Hübner, 1969, Aus der
Praxis. Umarbeitung von Wasserstoffverbindungen in abgeschlossenen
Rohren zu Wasserstoff für die massenspektrometrische Präzisionsanalyse
des Deuteriums im Bereich natürlicher Variationen. Isotopenpraxis, v. 5,
p. 35-36.

Gehre, M., R. Hoefling, and P. Kowski, 1996, Methodical studies for
D/H-isotope analysis - A new technique for the direct coupling of sample
preparation to an IRMS. Isot. Environ. Health Stud., v. 32, p. 335-340.

Finnigan MAT Application Flash Report No. G27 (1997) The H/Device, a
novel peripheral for measurements of D/H from microliter samples of
water and organic molecules.

I hope you can read German, since a reasonable number of the
publications is in German.

Best wishes,
Pier.
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Dr. P.A. de Groot
University of the Witwatersrand
Economic Geology Research Unit
Department of Geology
Private Bag 3
2050 Johannesburg
South Africa
Tel. +27 11 7162564
Fax. +27 11 3391697
E-mail <[log in to unmask]>

Visit the combined HOME-PAGE of EGRU-Geology on the Internet:
  http://www.wits.ac.za/science/geology/index.htm
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