@inbook{10.2307/j.ctt7rq7h.14,
ISBN = {9780691149929},
URL = {http://www.jstor.org/stable/j.ctt7rq7h.14},
abstract = {Imagine you wish to make a circular or spherical object but cannot simply use compasses to mark one out. Alternatively, you might have already made something round and wish to check the accuracy of your construction. We all know what a circle is, so here we discuss the problem of determining if what is supposed to be circular is really circular, and within what limits. This matters a lot in engineering applications of all sorts but particularly with rotating shafts and their bearings.So let us begin with an experiment for which you need a United Kingdom 50p (or 20p)},
bookauthor = {John Bryant and Chris Sangwin},
booktitle = {How Round Is Your Circle?: Where Engineering and Mathematics Meet},
pages = {188--226},
publisher = {Princeton University Press},
title = {HOW ROUND IS YOUR CIRCLE?},
year = {2008}
}