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Title: Beyond spherical top hat collapse
http://arxiv.org/abs/1008.1196http://arxiv.org/abs/1008.2246 by T. S. Pereira, R. Rosenfeld, A. Sanojahttp://arxiv.org/find/gr-qc/1/au:+Elst_H/0/1/0/all/0/1
Title: Lemaitre-Tolman-Bondi dust spacetimes: Symmetry properties and some extensions to the dissipative case
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