But if it wasn't for Mr. Euler -- who wrote almost 70 volumes of mathematics and had 13 children, who he apparently would dandle on his knee while he was writing -- if it wasn't for Mr. Euler, there wouldn't perhaps be these invariants.
Ma se non fosse stato per Eulero -- che scrisse quasi 70 volumi di matematica ed ebbe 13 figli, che faceva dondolare  sulle ginocchia mentre scriveva -- se non fosse stato per Eulero,  forse questi invarianti non esisterebbero.