RWD 6, photo from <a href="https://en.wikipedia.org/wiki/Challenge_1932" class="extiw" title="en:Challenge 1932">Challenge 1932</a>
Unknown author<span style="display: none;">Unknown author</span>
Glass, Andrzej, Adam Jońca, and Janusz Czerniak. 1984. "Polskie skrzydła". Warszawa: Wydawnictwo Interpress.