 Complete the following phrase:  Alelyukhin provided air cover during the Soviet occupation of Bessarabia and Northern Bukovina during June and July 1940, still with the 69th Fighter Aviation Regiment. The regiment was equipped with Polikarpov I-16 fighters. On 22 June 1941, Germany invaded the Soviet Union in Operation Barbarossa. Bessarabia was now on the front line at Alelyukhin fought in the 