Every function having bounded mean oscillation (BMO) on the line is written as a sum of coefficients times normalized rational functions with the coefficients satisfying a Carleson measure packing condition. This decomposition theorem and related techniques are used to obtain operator norm estimates for first and second order commutators and direct and converse singular value estimates for Hankel operators and products of Hankel operators. © 1986.
Rochberg, R., & Semmes, S. (1986). A decomposition theorem for BMO and applications. Journal of Functional Analysis, 67(2), 228–263. https://doi.org/10.1016/0022-1236(86)90038-8