1. Akkermans, A. D. L., Abdulkadir, S., and Trinick, M. J., 1978, Nitrogen-fixing root nodules in Ulmaceae, Nature, 274:190.
2. Akkermans, A. D. L. and Houwers, A., 1979, Symbiotic nitrogen fixers available for use in temperate forestry, in.: “Symbiotic Nitrogen Fixation in the Management of Temperate Forests,” J. C. Gordon, C. T. Wheeler, and D. A. Perry, eds., Forest Research Laboratory, Oregon State University, Corvallis.
3. Akkermans, A. D. L., Roelofsen, W., and Blom, J., 1979, Dinitrogen fixation and ammonia assimilation in actinomycetous root nodules of Alnus glutinosa, in: “Symbiotic Nitrogen Fixation in the Management of Temperate Forests,” J. C. Gordon, C. T. Wheeler, and D. A. Perry, eds., Forest Research Laboratory, Oregon State University, Corvallis.
4. Anonymous, 1976, Proceedings of the Bear Clover Conference, Stanislaus National Forest, March 17, 1976.
5. Bond, G., 1971, Fixation of nitrogen in two African species of Myrica, New Phytol., 70:1.