Lyle Gifford Boyd, The World of Flying Saucers: A Scientific Examination of a Major Myth of the Space Age (1963)
“ To the driver of a car on a dark country road, a single light suddenly appearing ahead may241 indicate a plane or a star low in the sky or something on the road itself—a motorcycle, a car with only one headlight working, a workman’s lantern, a pedestrian carrying a flashlight, or something else. A double light may mean another automobile, two motorcycles traveling parallel, an animal whose eyes shine in the approaching headlight, or something else. ”
