Derivatives of secondary classes and 2-normal bundles of foliations (Q2786748)

The author develops a framework in which derivatives of secondary characteristic classes of foliations are treated as secondary classes of foliations and their deformations. The paper presents the theory for transversely holomorphic foliations, although the theory for smooth real foliations is, as the author assures, similar. The very precisely presented theory is supplemented with extensive bibliography. However, one important item is missing [\textit{S. Hurder}, Invent. Math. 66, 313--323 (1982; Zbl 0489.57006)].