28. Y.L. Wang, X.L. Wu, C.-C. Chen and C.M. Lieber, “Enhancement of the critical current density in single-crystal Bi2Sr2CaCu2O8 superconductors by chemically induced disorder,” Proc. Natl. Acad. Sci. USA 87, 7058-7060 (1990).
27. Z. Zhang, Y.L. Wang, X.L. Wu, J.L. Huang and C.M. Lieber, “Electronic effect of lead substitution in single-crystal Bi(Pb)-Sr-Ca-Cu-O superconductors determined by scanning tunneling microscopy,” Phys. Rev. B 42, 1082-1085 (1990).
26. X.L. Wu, Z. Zhang, Y.L. Wang and C.M. Lieber, “Structural and electronic role of lead in (PbBi)2 Sr2CaCu2O8 superconductors by STM,” Science 248, 1211-1214 (1990).
25. H. Chen, X.L. Wu and C.M. Lieber, “Scanning tunneling microscopy investigations of the local electronic and structural effects of iron substitution in tantalum disulfide,” J. Am. Chem. Soc. 112, 3326-3332 (1990).
24. X.L. Wu and C.M. Lieber, “Direct observation of growth and melting of the hexagonal-domain charge-density-wave phase in 1T-TaS2 by scanning tunneling microscopy,” Phys. Rev. Lett. 64, 1150-1153 (1990).
23. X.L. Wu and C.M. Lieber, “Direct characterization of charge-density-wave defects in titanium-doped TaSe2 by scanning tunneling microscopy,” Phys. Rev. B 41, 1239-1242 (1990).