Mykolenko, Dmytro. " How did Ferdinand I of Saxe-Coburg‑Gotha become Frenchman?" Universum Historiae et Archeologiae = The Universe of History and Archeology = Універсум історії та археології = Универсум истории и археологии ISSN 2664-9950 (Print) ISSN 2707-6385 (Online) [Online], Volume 2 Number 2 (14 October 2020)