**Petr Honzík**

University of Missouri

Homogeneous Calderón-Zygmund kernel is a convolution
kernel of the type

where is an integrable function with mean zero on the unit sphere . It is well known that the corresponding convolution operator is bounded on if and only if the convolution

is essentially bounded. We provide an example that shows that on , , the condition () is no longer sufficient.

2005-05-23