Perturbation of a class of CR structures of codimension larger than one
The author, using techniques developed by \textit{H. Jacobowitz} and \textit{F. Treves} in Hokkaido Math. J. 12, 276-292 (1983; Zbl 0564.32010) proves the existence of a class of realizable CR structures, with dimension and codimension larger than one, that can be perturbed into non realizable CR structures.
scientific article; zbMATH DE number 515250