Several examples of one-dimensional analytic sets of uniqueness for harmonic functions on the sphere in ℝ3 are given and some examples of analytic sets on the sphere in ℝn which cannot contain sets of uniqueness are presented. Analytic curves which are sets of uniqueness for real-analytic functions in ℝn, n ≥ 3, are constructed. The obtained results are used to justify the inhomogeneity sounding schemes when the inverse problem of acoustic scattering is solved under the conditions that the source and detector coordinates coincide.