LAUSR

there exists a unique function q̃ ∈ L2(0, π) such that ω = ?̃? and {K̃,Ñ} are the Cauchy data of q̃.” The reason of condition (*) is that the Cauchy data are related with the constant ω by the relation ∫ π 0 K(t)dt = ω. This relation holds, since the function η1(λ) defined by formula (9) in the original paper is analytical at λ = 0. Adding condition (*) does not influence on the application of Proposition 3.7 in the proof of Theorem 3.1, because relation (28) for n = 0 implies ∫ π 0 K̃(t)dt = ω.