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D. C.  Robertson and Robertson, J. A., ?Ultrastructure of Pterospora andromedea Nuttal and Sarcodes sanguinea Torrey mycorrhizas?, New Phytol., vol. 92, pp. 539 - 551, 1982.

J. R.  Leake, McKendrick, S. L., Bidartondo, M., and Read, D. J., ?Symbiotic germination and development of the myco-heterotroph Monotropa hypopitys in nature and its requirement for locally distributed Tricholoma spp.?, New Phytol., vol. 163, pp. 405 - 423, 2004.