Im taking a course in contiuum mechanics and had some questions that im sure are pretty basic but I'm not getting. We just started curvilinear coordinates and I was curious if someone could explain in a little simplier language of what the superscript and subscripts mean. Or if you happen to know of a site that explains it that would be swell too. I found refrences to this paper (http://arxiv.org/abs/math.HO/0403252) several times while searching, but the paper doesnt seem to help me. (important stuff starts on page 38). Thanks for any help.