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 We refer to conversations with V. Lebedev and G. Volovik, to reports of the referees on Ref. , as well as the attempt by V. Lebedev and V. L'vov (see arXiv:1005.4575) to construct counter-arguments to our proof (we note in passing that the inconsistency of these counter-arguments is explained in our arXiv:1006.1789; Lebedev, L'vov, and Nazarenko do not agree with this explanation [arXiv:1007.3191]).