Ph.D. thesis of Maria Karzova was done within collaboration between Moscow State University and Ecole Centrale de Lyon and was supported by French government (so-called "cotutelle" program). Vera A. Khokhlova supervised Maria in Russia while Philippe Blanc-Benon was a scientific advisor in France. A French jury headed by Professor Daniel Juve came to Moscow to attend the Ph.D. defense of Maria. Finally, Maria got Ph.D. from both Moscow State University and Ecole Centrale de Lyon. Our congratulations to Dr. Karzova!