Rebecca Schulman Shaun Lee Nick Papadakis Erik Winfree One Dimensional Boundaries for DNA Tile Self-Assembly. 108-126 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2943&spage=108 2003 conf/dna/2003 DNA db/conf/dna/dna2003.html#SchulmanLPW03