Before revision: Among the researchers of the 20th century this idea was shared by professor Mikhail Tikhomirov, and professor Rybakov, in confirmation of the Slavic origin of the prince, the name Oskold derived from the name of the river Oskil, and therefore in his opinion it would be correct to use not "Askold", but exactly "Oskold", as it is found in the Old Rus' chronicles (or "Oskolod" – as indicated in the Nikiforov Chronicle of the XV century, Suprasl Chronicle of the XVI century or medieval Polish chronicle of Maciej Stryjkowski).
After revision: Among the researchers of the 20th century this idea was shared by professor Mikhail Tikhomirov, and professor Rybakov, in confirmation of the Slavic origin of the prince, the name Oskold derived from the name of the river Oskil, and therefore in his opinion it would be correct to use not "Askold", but exactly "Oskold", as it is found in the Old Rus' chronicles (or "Oskolod" – as indicated in the Nikiforov Chronicle of the 15th century, Suprasl Chronicle of the 16th century or medieval Polish chronicle of Maciej Stryjkowski).