@article {MATHEDUC.02305419,
author = {Webb, M. and Miller, D.},
title = {Parallel curves at infinity.},
year = {1994},
journal = {Pi Mu Epsilon Journal},
volume = {10},
number = {1},
issn = {0031-952X},
pages = {39-41},
publisher = {Worcester Polytechnic Institute (WPI), Mathematical Sciences, Worcester, MA},
abstract = {Let $\beta{}$(t) = (x(t), y(t)) denote a smooth curve in $R^2$. We will say that a curve $\beta_r$ is r-parallel to $\beta{}$ if $\beta_r(t)=\beta(t)+rN(t)$ where $N(t)=(-y\rq(t),x\rq(t))/\sqrt{(x\rq(t))^2+(y\rq(t))^2}$. In this note we will show that at infinity all r-parallel curves are circles. (orig.)},
msc2010 = {I65xx},
identifier = {1995a.00375},
}