Dallas, TX (1970), Nice, France (1973), Warsaw, Poland (1977),

Linz, Austria (1981), Gaithersburg, MD (1989),

Southampton, UK (1992), Santa Fe, NM (1995),

Shanghai, China (1997), Berlin, Germany (1999),

Kanazawa, Japan (2001), Buffalo, NY (2003),

Toulouse, France (2005), Guildford, UK (2007),

Sendai, Japan (2009)