``STM investigations on compact Au/sub 55/ cluster pellets'' Houbertz R, Feigenspan T, Mielke F, Memmert U, Hartmann U, Simon U, Schon G, and Schmid G, Europhys. Lett. (Switzerland) 28, 641-6, (1994).
``A fascinating new field in colloid science: small ligand-stabilized metal clusters and possible application in microelectronics. 1. State of the art. '' Schoen G and Simon U, Colloid Polym. Sci. (Germany) 273, 101-17, (1995).