On Tue, 4 Oct 2005 apw@ap-woolrich.co.uk wrote:
The following argument is not valid. I can think of several titles relevant to the the history of technology which are not in the BL catalogue, and not listed on the C19 Short Title Catalogue which covers a range of copyright libraries. This is particularly true for trade catalogues which are outside outside UK copyright deposit rules and so never recorded.
Then where should one turn to verify that these books exist? Is there the information in an online database? Or even a printed reference work that would be available at a large public or college library?
The whole point of proving a citation is to allow others to either confirm or extend our research. If they can't find a copy of the material cited, then the citation isn't very useful. That's the reason unpublished materials or private conversations aren't permitted sources in Wikipedia.
Unless we can verify that the source exists, then we might as well allow every kook in who cites this certain book that was printed a few years ago, but almost every copy has been destroyed, & the publisher was forced out of business. (Or claims that it was given to him by an angel, a crewman of a UFO, or a talking salamander.)
Geoff