A mathematical treatment by which the author claims `it is possible to generate and study an entire class of valid solutions of any phase retrieval problem'. Although the method is said to have applications in X-ray crystallography, the examples given are for one-dimensional functions and it is not at all clear that the method, which is based on the solution of a system of n linear equations in n unknowns, can generate and determine the unique solution for a diffraction experiment that leads to the correct atom-based model in three dimensions.