George Adamski was a Polish-born American, known as the original “contactee,” a person who claims to have met aliens in person.
He said he met a Venusian in the California desert in 1952, and his co-authored book Flying Saucers Have Landed (1953) became a worldwide bestseller. The bell-shaped saucer he said he photographed is called the “Adamski-type saucer.” For details, see the encyclopedia entry George Adamski.