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439­451 (2000).
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21. Painter, O. et al. Two-dimensional photonic band-gap defect mode laser. Science 284, 1819­1821
(1999).
22. Ryu, H.-Y. et al. Square-lattice photonic band-gap single-cell laser operating in the lowest-order
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Acknowledgements This work was supported by the Netherlands Organization for Scientific
Research (NWO) through the `NRC photonics' grant.
Competing interests statement The authors declare that they have no competing financial
interests.
Correspondence and requests for materials should be addressed to M.H. (m.t.hill@tue.nl).
..............................................................
Prolonged KREEP magmatism on the
Moon indicated by the youngest
dated lunar igneous rock
Lars E. Borg1
, CharlesK. Shearer1
, YemaneAsmerom2
&James J. Papike1

Source: Asmerom, Yemane - Department of Earth and Planetary Sciences, University of New Mexico

Collections: Geosciences