Lvov-Sandomierz Offensive
The Lvov–Sandomierz offensive or Lvov–Sandomierz strategic offensive operation (Russian: Львовско-Сандомирская стратегическая наступательная операция) was a major Second World War operation by the Soviet Red Army to force German troops from Ukraine and Eastern Poland. The operation was launched in mid-July 1944, and successfully completed by the end of August.
Source: Wikipedia — Lvov-Sandomierz Offensive (CC BY-SA 4.0)