Prof. dr hab. Ryszard Urbański is staying in New York from 2007-04-10 to 2007-04-17, where on 14th and 15th of April he is taking part in the international conference organised by AMS, during which he is holding the lecture entitled "Pairs of compact convex sets".
Dr Jerzy Grzybowski visited the Chair of Approximation Theory of the Institute of Mathematics of Jagiellonian University on 2006-12-13, where he held the lecture entitled: "On existence and uniqueness of a minimal representation of the difference of sublinear functions".