The volume "Rare Earth Elements" C 11 deals with the compounds and systems of the rare earth elements with boron, Le., borides, borates, and associated alkali double compounds. As in all earlier volumes of "Rare Earth Elements" Se ries C ("Seltenerdelemente" Reihe Cl, comparative data are presented in sections preceding treatment of the individual compounds and systems. Topics of the present volume C 11 aare the comparative data on the borides and...