http://dcherukhin.i2p/research/research.htm
In the first model, only linear elements with arbitrary number of inputs
are allowed, whereas in the second one, any Boolean elements can be
present. These methods are applicable to matrices with sufficiently large
Hamming distance between the rows, for example, to the Hadamard matrices. Нижняя оценка сложности в классе схем
глубины 2 без ограничений на базис //
Вестник МГУ.