Elliot, R.M. et al. (1998) Rhizobium issues affecting the contribution of caucasian clover to New Zealand pastoral agriculture. Proceedings of the New Zealand Grassland Association 60: 207-211 https://www.grassland.org.nz/publications/nzgrassland_publication_241.pdf
Nguyen, T. D. (2020). Characterisation of rhizobia associated with Sophora, Trifolium ambiguum and Genisteae legumes in New Zealand and assessment of their importance to nitrogen assimilation at Lincoln University of European Broom and Sophora microphylla: A thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy (Doctoral dissertation, Lincoln University).