Klaus Bürgle (1926-2015) was a German artist best known for his retro-futuristic depictions of Moon bases and underwater worlds.
Bürgle started his one-man business after graduating from the State Academy of Fine Arts in Stuttgart in 1951. He specialized in technical and scientific drawings, illustrating science-fiction books and magazines published in Germany.
There is not much information about Bürgle online in English. Ralf Bülow and Michael Peters have a lot of his art at their excellent Retro-Futurismus.