Summer temperature trend over the past two millennia using air content in Himalayan ice - Hou, S.; Chappellaz, J.; Jouzel, J.; Chu, P. C.; Masson-Delmotte, V.; Qin, D.; Raynaud, D.; Mayewski, P. A.; Lipenkov, V. Y.; Kang, S. (Clim. Past, 2007)