“What Were the Flying Saucers?”,
August 1951 (Popular Science, New York City)
In this article, Popular Science speculates about the nature of flying saucers:
http://books.google.com/books?id=lyEDAAAAMBAJ&pg=PA74&dq=what+were+the+flying+saucers&hl=en&ei=KQW5TeycD8nJswbEpLzrAw&sa=X&oi=book_result&ct=result&resnum=1&ved=0CDMQ6AEwAA#v=onepage&q=what%20were%20the%20flying%20saucers&f=false
The article presents one of the two 1950 McMinnville, Oregon UFO photos.
UFO photographed over McMinnville, Oregon on 11 May 1950,
at 7:30 p.m. (ufoera.com photo)