Acknowledgements
The authors wish to express their thanks to Olga Stepankova, Sona Krizkova and Lenka Vyslouzilova for helpful discussions and suggestions.
Financial & competing interests disclosures
The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.
No writing assistance was utilized in the production of this manuscript.