@article{purcino_festin_elkan_2000, title={Identification of effective strains of Bradyrhizobium for Arachis pintoi}, volume={77}, number={4}, journal={Tropical Agriculture}, author={Purcino, H. M. A. and Festin, P. M. and Elkan, G. H.}, year={2000}, pages={226–231} }
 @book{elkan_2000, title={Microbial evolution: A narrative history of microbiology at North Carolina State University}, publisher={Raleigh, NC: Published by North Carolina Agricultural Foundation, Inc}, author={Elkan, G. H.}, year={2000} }
 @book{elkan_upchurch_1997, title={Current issues in symbiotic nitrogen fixation: Selected papers of the 15th North American Conference on Symbiotic Nitrogen Fixation held at North Carolina State University, Raleigh, NC, USA, 13-17 August 1995}, publisher={Dordrecht; London: Kluwer Academic}, author={Elkan, Gerald H. and Upchurch, R. G.}, year={1997} }
 @article{elkan_1992, title={Taxonomy of the rhizobia}, volume={38}, DOI={10.1139/m92-075}, number={6}, journal={Canadian Journal of Microbiology}, author={Elkan, G. H.}, year={1992}, pages={446} }
 @inbook{elkan_bunn_1992, title={The Rhizobia}, ISBN={0387972587}, booktitle={The Prokaryotes : a handbook on the biology of bacteria : ecophysiology, isolation, identification, applications}, publisher={New York : Springer-Verlag}, author={Elkan, G. H. and Bunn, C. R.}, year={1992}, pages={2197} }
 @inbook{elkan_kuykendall_1982, title={Carbohydrate metabolism}, ISBN={9780198545552}, booktitle={Nitrogen fixation.Volume 2.Rhizobium}, publisher={Oxford: Clarendon Press}, author={Elkan, G. H. and Kuykendall, L. D.}, year={1982}, pages={147} }
 @article{elkan_1971, title={Biochemical and genetical aspects of the taxonomy of Rhizobium japonicum}, DOI={10.1007/bf02661842}, journal={Plant and Soil}, author={Elkan, G. H.}, year={1971}, pages={85} }