1. Institute of Chemistry Education, Justus-Liebig-University Giessen, Giessen, Germany
2. Department of Chemistry, Fort Hays State University, USA
3. School of Chemistry & Molecular Biosciences, The University of Queensland, St Lucia 4072, Australia
4. Department of Chemistry, University of South Florida, USA
5. Department of Chemistry and Biochemistry and School of Education, North Dakota State University, USA