Perhaps white car is one of the two blacks ones...but the two blacks are quite different one each other; the grille of the picture offered as a clue from Saco has a sort of rays all around, missing in the one posted by Wendax; the first one has aluminium mouldings missing in the second one; the second one has just half windscreen. Blacks have white steering wheels, the white one has it black.
Then there is the wheels question; I think it is possible that the white car (that's for sure a Zagato) is a different car, perhaps realized on 1100 base...who knows.