H∞ Ring Spectra and their Applications Extended powers and H ring spectra Miscellaneous applications in stable homotopy theory Homology operations for H and Hn ring spectra The homotopy theory of H ring spectra The homotopy groups of H ring spectra The adams spectral sequence of H ring spectra H ring spectra via space level homotopy theory Power operations in H  d ring theories The mod p k theory of QX.