space of bounded measures for n> 1 [3], we show in this paper that it fails to contain certain
natural operators of the singular integral type (Theorem 1). To prove this, we consider the
analogous Sobolev space W̊ k, 1 of the homogeneous type and show that a nonconstant
homogeneous function of degree zero cannot be a Fourier multiplier of W̊ k, 1 (R
n)(Theorem 2). Some of the results of this paper were announced in [4].