Our friends and their materials: Chan Yip Cheung http://www.geogebra.org/mathchan.cuhk 黃德鳴 http://www.geogebra.org/mingshuk Eric Chiu http://www.geogebra.org/chericiu Cherie http://www.geogebra.org/cherieching Lamberto Lamberti http://tube.geogebra.org/lamberto+lamberti TSANG WING SHAN FELIX http://www.geogebra.org/felixtws Tsang Kin Fun http://www.geogebra.org/tsangkinfun Arthur Lee http://www.geogebra.org/msalee Alex CHIK http://www.geogebra.org/alexchik Anthony Or http://www.geogebra.org/orchiming |