Reports on Mathematical Physics 69/3/2012

Topological properties of operator generalized effect algebras
Lorentzian manifolds having the killing property
General formula for symmetry factors of Feynman diagrams
On the spectrum of the Schrodinger Hamiltonian of the one-dimensional harmonic oscillator perturbed by two identical attractive point interactions
The logic order on a generalized Hermitian algebra
The truncation and renormalizability of the superstring and heterotic string effective actions
Necessary conditions for optimality of decomposable entanglement witnesses