"X-ray Structural Analysis of Semiconductor Interfaces", Extra Colloquium, FOM Institute, February 1991
"Surfaces and Interfaces, Part III", HERCULES, Grenoble, France, March 1991
"X-ray diffraction Experiments on the Clean and H-induced Structures", The {100} Surface of Tungsten, ESF Workshop, Cambridge, UK, March 1991
"The Pt(110) Surface Phase Transition", March Meeting of the American Physical Society, Cincinnati, April 1991
"Metal Surfaces at Elevated Temperatures", Physics Colloquium, University of Washington, April 1991
"X-ray Diffraction from Semiconductor Surfaces and Interfaces", Solid State Seminar, University of Washington, April 1991
"Surface Diffraction on Semiconductor Surfaces and Interfaces", International Conference on Formation of Semiconductor Interfaces, Rome, May 1991
"X-ray Diffraction Analysis of Surface and Interface Structures", IESS-CNR, Rome, May 1991
"Extended X-ray Reflectivity Analysis of Si(111)7x7" International Conference on Surface X-ray and Neutron Scattering, Bad Honef, Germany, June 1991.
"Metal Surfaces at Elevated Temperatures", Solid State Seminar, University of Arhus, Arhus, Denmark, June 1991
"Metal Surfaces at Elevated Temperatures", Applied Physics Seminar, Danish Technical Highschool (DTH), Lyngby, Denmark, June 1991.
"Facet Dynamics on the Ag(111) Surface", NSLS Lunch Seminar, Brookhaven, September 1991
"Semiconductor Surface and Interface Structures by X-ray Diffraction", Ecole Polytechnique Fédérale, Lausanne, Switzerland, September 1991
"X-ray Characterization Methods", Workshop on Epitaxy, Interfaces, Defects and Processing of Electronic and Photonic Materials, Pittsburgh, November 1991
"X-ray Studies of Thin-Film Growth and Semiconductor Interface Structure", Tsukuba Research Consortium, Tsukuba, Japan, November 1991
"Structural Analysis of Semiconductor Interfaces by X-ray Diffraction", Symposium on Atomically Controlled Surfaces and Interfaces, Tokyo, November 1991
"X-ray Studies of Thin-Film Growth and Semiconductor Interface Structure, Physics Department Seminar, Hong Kong University of Science and Technology, Hong Kong, November 1991
"Silicon Surfaces and Interfaces Studied with X-Ray Methods", Symposium on Advanced Science and Technology of Silicon Materials, Kona, HI, November 1991