[piaste]

That's correct. In practice we would often rephrase to avoid the double 'la', not because it's grammatically incorrect but because it is awkward to read (less so in speech). Compare:

French: C'est une citation de De Gaulle.

German: Das ist ein Zitat von Von Neumann.

Both correct, but one would probably add "Charles" or "John" between the two 'de' or 'von' just to break them up.