After Stepanov's death in 1896, the dancer Alexander Gorsky took over the notation project and perfected Stepanov's system. After Gorsky departed St. Petersburg in 1900 to take up the post of Ballet Master to the Bolshoi Theatre of Moscow, the former dancer of the Imperial Theatres Nicholas Sergeyev took over the project as supervisor. By 1903 Sergeyev was appointed "régisseur" of the Imperial Ballet. It was Sergeyev's assistants who created the majority of the notation, all of whom were dancers with the imperial ballet: Alexander Chekrygin (ru: Чекрыгин, Александр Иванович, Victor Rakhmanov, Nikolay Kremnev (ru: Николай Кремнев), and S. Ponomaryev (ru: С. Пономарев). The collection also includes notation created by students.