@article{10_1090_S0894_0347_99_00310_0,
     author = {Nazarov, F. and Treil, S. and Volberg, A.},
     title = {The {Bellman} functions and two-weight inequalities for {Haar} multipliers},
     journal = {Journal of the American Mathematical Society},
     pages = {909--928},
     year = {1999},
     volume = {12},
     number = {4},
     doi = {10.1090/S0894-0347-99-00310-0},
     url = {http://geodesic.mathdoc.fr/articles/10.1090/S0894-0347-99-00310-0/}
}