The organization I added is based on this source: http://mathmuse.sci.ibaraki.ac.jp/pattrn/Pattern2E.html . I'm sure that the organization, in concept, is not copyrightable; and I think that my wording is sufficiently different that I don't need to seek permission. But I could use some advice here. Maybe a link should be provided, in any case? Steve 04:06, 19 September 2007 (CDT)
I have in the past added a sentence saying something like "This material was adapted from the following source" - then give the reference. We should be able to quote or reference others as long as we properly attribute the original source I think. --Barta 08:31, 19 September 2007 (CDT)
Hmm. I think it's all ripped off from the original source, Symmetries of Culture by Washburn and Crowe, which everyone should take a look at - that's where all the flow charts come from too. That said, I see no point in citing some random internet site that also ripped it off. But probably I'll put in a citation for W&C somewhere. Bryan 21:13, 29 January 2008 (CST)
This page needs a better organizational scheme. In particular, how much and where to talk about the proof of the classification. Right now, it's in two places, before and after the big list of 17 groups. We also have 3 links to Baloglou's proof. The material in the two sections that talk about it is pretty much complementary, so we should merge into one. Bryan 10:02, 11 February 2008 (CST)
Whether a WP group has glide reflections
It is somewhat misleading to say a WP group has no glide reflections when in fact it does. For example, pm has glide reflections, since a reflection across a line followed by a translation along that line is a glide reflection. Need to figure out a neater way to say it.