"Сім чудес України визначено!" [The seven wonders of Ukraine have been determined!] (in Ukrainian). 22 August 2007. Archived from the original on 25 August 2007. Retrieved 10 September 2023.
encyclopediaofukraine.com
"Ostroh". Internet Encyclopaedia of Ukraine. Canadian Institute of Ukrainian Studies. Retrieved 10 September 2023.
"Сім чудес України визначено!" [The seven wonders of Ukraine have been determined!] (in Ukrainian). 22 August 2007. Archived from the original on 25 August 2007. Retrieved 10 September 2023.