- On the Casmir Operators Associated with Any Lie Algebra
- Unified Free Quantum Fields for Massive and for Massless Particles
- A no-go theorem concerning the cluster decomposition property of direct-interaction scattering theories
- Position operators for the relativistic non-interacting n-particle system
- Representations of groups with subgroups of index 2
- On the irreducible representations of groups containing a subgroup of finite index
- A covariant description of particle position
- Repeated measurements in quantum theory
- Relativistic quantum mechanics of n-particle systems with cluster-separable interactions
- On the commutant of an irreducible set of operators in real Hilbert space
- Rigidly connected overlapping spherical particles: a versatile grain model