Residual internal stress in partially crystallized photothermorefractive glass: evaluation by nuclear magnetic resonance spectroscopy and first principles calculations - Zwanziger, J. W.; Zwanziger, U. Werner; Zanotto, E. D.; Rotari, E.; Glebova, L. N.; Glebov, L. B.; Schneider, José Fabian (Journal of Applied Physics, 2006)