In the article “Results of the first stage of an experimental study of the structure of crystals” (in the note on page 361) the principle of determining the structure from a parallelohedron of the smallest volume is established, which is equivalent to the principle of establishing a system of parallelohedrons of the highest order permissible for a given regular system of points. A criterion for the correct construction of a parallelohedron can be a test of the possibility of another, more special, arrangement of one of the atoms represented in the chemical formula in the smallest number, or, even better, if there are no single atoms, the placement of that special point that occupies a single position in the parallelohedron.
