Letter 720a – January 8/20 1878, from San Remo
Letter 822a – May 1/13 1878, from Kamenka
Letter 1168a – April 30/May 12 1879, from Kamenka
Letter 4019 – January 30/February 11 1890, from Florence
All are drafts. The first, third and last were not sent; the second may not have been.
And one photograph, by Ivan Dyagovchenko, July 24/August 5 1877, Moscow:
Sixteen letters from Antonina Tchaikovskaya to the composer, dating from 1877 to 1890, are preserved in the Klin House-Museum Archive.