C. Rohr, M. Balbas Gambra, K. Gruber, E. C. Constable, E. Frey, T. Franosch, B. A. Hermann: Molecular Jigsaw: Pattern Diversity Encoded by Elementary Geometrical Features. 2010Nano Letters: 10. ISBN 1530-6984 http://dx.doi.org/10.1021/nl903225j