Phase-contrast X-ray microtomography links Cretaceous seeds with Gnetales and Bennettitales

@article{Friis2007PhasecontrastXM,
  title={Phase-contrast X-ray microtomography links Cretaceous seeds with Gnetales and Bennettitales},
  author={Else Marie Friis and Peter R. Crane and Kaj Raunsgaard Pedersen and Stefan Bengtson and Philip C. J. Donoghue and Guido W. Grimm and Marco Stampanoni},
  journal={Nature},
  year={2007},
  volume={450},
  pages={549-552}
}
Over the past 25 years the discovery and study of Cretaceous plant mesofossils has yielded diverse and exquisitely preserved fossil flowers that have revolutionized our knowledge of early angiosperms, but remains of other seed plants in the same mesofossil assemblages have so far received little attention. These fossils, typically only a few millimetres long, have often been charred in natural fires and preserve both three-dimensional morphology and cellular detail. Here we use phase-contrast… 

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