Christopher B. Caputo and Douglas W. Stephan : Non-conventional Lewis Acids and Bases in Frustrated Lewis Pair Chemistry // Andreas Phanopoulos, Nicholas J. Long, and Philip W. Miller : Triphosphine Ligands: Coordination Chemistry and Recent Catalytic Applications // Robert H. Crabtree : Sigma Bonds as Ligand Donor Groups in Transition Metal Complexes // Malcolm L.H. Green and Gerard Parkin > The Covalent Bond Classification Method and Its Application to Compounds That Feature 3-Center 2-Electron Bonds // Ghenwa Bouhadir, Didier Bourissou : Coordination of Lewis Acids to Transition Metals:Z-Type Ligands.