To my parents, grand-parents, Alex, Silke and Khrystia

A special thanks to : Yevgen Solonin, Yaroslav Hrytsak, Mrs. Sophie Fouace, Mrs. Jacqueline Brahic, Mrs. Irena Klouchkovska, Vlodko Kaufman, Anastasia Sirikova, Natacha Vovchenko, Francky Blandeau, Irma Inaridze, Nicolas Desagher, Jean-Claude Gayan, Marichka Dioura, Natalia Strilets, Oleksiy Kachmar, Luda Pawliw, Ihor Kozhan, Roman Chmelyk, Andrzej Zujewicz, Albert Lazaro-Tinaut, Anna Canter, Gilbert Dufois, Perrine Trullemans.