http://www.bartleby.com/65/bo/Bortnian.html Biographical article in the Columbia Encyclopedia, Sixth Edition, 2001. http://www.cyberhymnal.org/bio/b/o/r/bortniansky_ds.htm Biography and music with links to MIDI audio of the tune St. Petersburg. http://www.karadar.it/Dictionary/bortniansky.html Musica Classica classical music dictionary article. http://www.karadar.it/Operas/bortniansky.html Musica Classica listing of his operatic works, including the Italian libretto by Pietro Metastasio of Alcide.