On Lynden-Bell and Katz's definition of gravitational field energy Ø. Grøn Research Articles Pages: 889 - 897
Axially symmetricpp-waves and their interpretation as extended massless particles G. Lessner Research Articles Pages: 899 - 912
Normal modes of a model radiating system Kostas D. KokkotasBernard F. Schutz Research Articles Pages: 913 - 921
On conformally related fields in Rosen's bimetric gravitation theory Ilija Lukačević Research Articles Pages: 923 - 930
Perturbations of the Plebanski metric in general relativity. I. Equations for gravitational perturbations Mainuddin AhmedPatrick Dolan Research Articles Pages: 953 - 960
Perturbations of the Plebanski metric in general relativity. II. Perturbations of the fermion field Mainuddin AhmedPatrick Dolan Research Articles Pages: 961 - 970
Relativistic wave mechanics of spinless particles in a curved space-time G. CognolaL. VanzoS. Zerbini Research Articles Pages: 971 - 982
Spin-tensorial concomitants of the spin-tensor field R. J. NoriegaC. G. Schifini Research Articles Pages: 983 - 989