I had a British friend in Germany back in about 1980 with one of these, and at the time, they were as commonplace on surface streets (but NOT the Autobahn) as VW's here.
The engine was tiny. If I remember right, a 600 or 650cc boxer twin. A friend and I replaced the engine in my friend's car and the two of us easily swapped it out by hand.
Weird shifter in them, too. The shaft went horizontally through the dash and curved up inside the car to approximate the more familiar vertical shifter.
I wouldn't know for sure, but wouldn't Citroen be French for "Lemon"? Giving rise to the meaning of the word nowadays as it applies to cars?
Another notable thing about those (and all Citroens) is the very soft suspension with travel along the lines of what a motocross motorcycle has.