David Bremner Timothy M. Chan Erik D. Demaine Jeff Erickson Ferran Hurtado John Iacono Stefan Langerman Perouz Taslakian Necklaces, Convolutions, and <i>X</i> + <i>Y</i>. 160-171 2006 conf/esa/2006 ESA http://dx.doi.org/10.1007/11841036_17 db/conf/esa/esa2006.html#BremnerCDEHILT06