Electronic state of nitrogen incorporated into CNx nanotubes L. G. Bulusheva, A. V. Okotrub, A. G. Kudashov, I. P. Asanov and O. G. Abrosimov Eur. Phys. J. D, 34 1-3 (2005) 271-274 Published online: 13 July 2005 DOI: 10.1140/epjd/e2005-00156-y