Check for any recent scholarship or updated information. Assuming there isn't much, as he's from the late 19th-early 20th century, but still, avoid outdated information.
Avoiding inaccuracies: Need to ensure details about his paintings and projects are correct. For example, the Church of St. Alexander Nevsky in Moscow, did he work on its iconostasis? Yes, that's a known fact. Also, the Tretyakov Gallery has a collection of his works. aleksei valerevich kovalskii updated
Wait, some facts might be conflicting. For example, some sources say he worked on the Church of St. Alexander Nevsky, others mention different projects. Need to verify that. Also, his death date is 1913, correct? Lived through significant historical changes, from the 19th to early 20th century. Check for any recent scholarship or updated information