I'm not sure about names of pilots involved or the exact time of the event (but I can check out if necessary). However, I'm sure it happened in 1941 when Slovak pilots were flying Avia B.534 biplanes on Eastern front... One Slovak pilot was hit by ground fire and made forced landing in enemy held territory. His wingman landed in vicinity in order to rescue his fellow pilot. Anyway, rescue attempt was successfull and they managed to take off under enemy fire with downed pilot standing on lower wing and holding tightly for wing struts. They flew all the way to their base this way and after landing the downed pilot was in shock and scared to death, but alive.
On another similar occasion downed Slovak airman climbed into the cockpit next to the pilot as they flew to safety...