 Some of them who frequent or inhabit the subway have attracted international attention for learning how to use the trains to commute between various locations.The issue of Moscow's stray dogs was first mentioned by Russian writers such as journalist Vladimir Gilyarovsky in the late 19th century.Their sad lot was dramatised by Anton Chekhov in the famous short story "Kashtanka", by Mikhail Bulgakov in the novella "Heart of a Dog", and by Gavriil Troyepolsky in the novel "White Bim Black Ear".