1. Allègre, C. J. et al. Nature 307, 17–22 (1984).
2. Gu Quingge, He Guoxiang & Wang Yigang Paleontol. Sinica 355–356 (1982).
3. Xu, R-H et al. J. Geol. (submitted).
4. Girardeau, J. et al. Nature 307, 27–31 (1984).
5. Wang Naiwen in Résultats de la coopération franco-chinoise au Tibet (mission 1980) (eds Mercier, J. L. & Li Guangqin) (CNRS, Paris, in the press).