Because of this, at least until fairly recently there has been much less published material in English concerning the Eastern front, and very little on the air war there.
A terrific exception are Christer Bergstroms multi-volume set Black Cross - Red Star.


These definitive volumes, five at the moment, take the story from Barbarossa to Kursk, with more to come. First published over 20 years ago, the author is currently producing a second edition set which are virtually new volumes:
"The Black Cross/Red Star book series is the only documentation of the true air battle on the Eastern Front during World War II, based on a wealth of primary sources from both sides as well as interviews with a large number of veterans from both sides. The new Volume 2 has just been published. The new Volume 3 will be published next year, and then a new volume (6, 7 & 8 ) will follow each year. The whole series will be completed, and the history of the air war on the Eastern Front will have gone from rather unknown to one of the best documented phases in the history of air war."
You can read a sample from vol 2 here: https://vaktelforlag.se/wp-content/uplo ... xtract.pdf
You can order the books direct from the author here: https://vaktelforlag.se/produkt-kategori/english/