1. On quadratic first integrals of the geodesic equations for type {22} spacetimes

   • Martin Walker
   • Roger Penrose

   OriginalPaper Pages: 265 - 274

2. On the validity of ward identities

   • P. Stichel

   OriginalPaper Pages: 275 - 290

3. On the mathematical description of quantized fields

   • R. Ascoli
   • G. Epifanio
   • A. Restivo

   OriginalPaper Pages: 291 - 300

4. The conservation of matter in general relativity

   • Stephen Hawking

   OriginalPaper Pages: 301 - 306

5. Ultralocal scalar field models

   • John R. Klauder

   OriginalPaper Pages: 307 - 318

6. Non-factor quasi-free states of the CAR-algebra

   • J. Manuceau
   • A. Verbeure

   OriginalPaper Pages: 319 - 326