  Covariant equations characterizing the strength of a singularity in spherical
symmetry are derived and several models are investigated. The difference
between central and non-central singularities is emphasised. A slight
modification to the definition of singularity strength is suggested. The
gravitational weakness of shell crossing singularities in collapsing spherical
dust is proven for timelike geodesics, closing a gap in the proof.

General Relativity and Quantum Cosmology