Large convexly independent subsets of Minkowski sums. Swanepoel, Konrad J.; Valtr, Pavel — 2010 The Electronic Journal of Combinatorics [electronic only]
Unit Squares Intersecting All Secants of a Square. Pavel Valtr — 1994 Discrete & computational geometry
Low-distortion embeddings of trees. Babilon, Robert; Matoušek, Jiří; Maxová, Jana; Valtr, Pavel — 2003 Journal of Graph Algorithms and Applications