但当他深入研究自己的研究成果时，却发现他对非洲土壤的认识有50%来自非洲研究者，而这些研究人员的成果没有也不可能在国际学术期刊上发表。
When he dug deeper into his own research, he found that 50% of what he had learned about African soil came from African researchers, who have not or could not publish their work in international academic journals.