What is the author's style in Burger's Daughter by Nadine Gordimer?

The point of view has a fairly unique feature in using much switching from first to third person. For much of the text a first person point of view is used, while these parts alternate with other sections where a third person general observer point of view is used. A distinct shift is created by using a different person for Rosa to address her inner thoughts to in each of the three parts of the book. In the largest part of the book, Part I, Rosa, using a first person viewpoint, addresses her inner thoughts to Conrad repeatedly and explicitly, although Conrad is present in the book in scenes only from pp. 17 to 70.