Who dated Grand Duke Nicholas Nikolaevich of Russia (1831–1891)?

Grand Duke Nicholas Nikolaevich of Russia (Russian: Великий князь Николай Николаевич; 8 August 1831 – 25 April 1891) was the third son and sixth child of Tsar Nicholas I of Russia and Alexandra Feodorovna. He may also be referred to as Nicholas Nikolaevich the Elder to tell him apart from his son, Grand Duke Nicholas Nikolaevich of Russia (1856–1929). Trained for the military, as a Field Marshal he commanded the Russian army of the Danube in the Russo-Turkish War, 1877–1878.