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I have try a diagram (request removed) Rocchini 16:00 6 june 2007 (UTC)

Hey, the diagram looks really nice, but it isn't correct --or at least it doesn't convey to the reader a clear idea: one edge should be in A the other in B. It looks as though one edge is in the intersection of A and B while the other is not in A or B. The diagram should be removed until it is made right. Geminatea 00:50 20 october, 2008 —Preceding undated comment was added at 04:49, 20 October 2008 (UTC). reply

Is this article a stub? Jfarr11 07:01, 6 February 2007 (UTC) reply

Yes. Orthografer ( talk) 15:19, 17 April 2010 (UTC) reply