1 E.. Myers, H.S. Margolis, J.K. Thompson, M.. Farmer, J.D. Silver, and M.R. Tarbutt, Physical Review Letters 82, (1999).
1 E.. Myers, J.K. Thompson, E.. Gavathas, N.R. Claussen, J.D. Silver, and D.. Howe, Physical Review Letters 75, (1995).