Czechoslovak Avia Bk-534 fighter aircraft.
Pseudonymous – published under a corporate name – Avia
2016-06-17
Ing. Jiří Vraný – Avia B-534, MBI 1994, <a href="//commons.wikimedia.org/wiki/Special:BookSources/80-901263-6-7" title="Special:BookSources/80-901263-6-7">ISBN 80-901263-6-7</a>.