1. Scuola Normale Superiore di Pisa, Piazza dei Cavalieri 7, 56126 Pisa, Italy
2. Department of Optics, Palacký University Olomouc, 17. listopadu 12, 77146 Olomouc, Czech Republic
3. Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Flemingovo náměstí 2, 16610 Prague, Czech Republic