A statement regarding O.R. being the main source for all of the listings was added a couple of versions prior to this one


L.W. Heck reference - where used in list?

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Cannot find a version that lists where the Heck reference is used. --KeithB 15:12, 20 November 2006 (UTC)Reply

This version is the old version that adds a large number of references. --KeithB 15:15, 20 November 2006 (UTC)Reply

Found this external link at the USGS. The date on this version (1966) is difference than the article reference listing (1955). --KeithB 15:49, 20 November 2006 (UTC)Reply