The bilinear Hilbert trasform is pointwise finite.
Michael T. Lacey (1997)
Revista Matemática Iberoamericana
Similarity:
Let f ∈ L∞ and g ∈ L2 be supported on [0,1]. Then the principal value integral below exists in L1. p.v. ∫ f(x + y) g(x - y) dy / y.