1. Bir, S. S. and Chatha, G. S. 1985. SOCGI plant chromosome number reports III. J. Cytol. Genet. 20: 204–205.
2. Bir, S. S., Gill, B. S. and Bedi, Y. S. 1984. Cytological Studies in Some Western Himalayan Woody Species. I. Gamopetalae and Monochlamydae. In: Paliwal, G. S. (ed.). The Vegetational Wealth of the Himalayas. Puja Publishers, Delhi. pp. 483–496.
3. Bir, S. S., Gill, B. S., Bedi, Y. S. and Singhal, V. K. 1980. Evolutionary Status of the Woody Taxa of Garhwal Himalaya. In: Khosla, P. K. (ed.). Improvement of Forest Biomass Indian Society of Tree Scientists, Solan. pp. 81–96.
4. Chatha, G. S. and Bir, S. S. 1987. Population analysis of some woody species from Palni Hills, South India. J. Cytol. Genet. 22: 83–94.
5. Duangjai, S., Samuel, S. R., Munzinger, J., Forest, F., Wallnöfer, B., Barfuss, M. H. J., Fischer, G. and Chase, M. W. 2009. A multi-locus plastid phylogenetic analysis of the pantropical genus Diospyros (Ebenaceae), with an emphasis on the radiation and biogeographic origins of the New Caledonian endemic species. Mol. Phylogenet. Evol. 52: 602–620.