我们追踪了这个问题的来源。

Wǒmen zhuīzōng le zhège wèntí de láiyuán.

We traced the origin of this issue.

这些化石的来源尚未被揭示。

Zhèxiē huàshí de láiyuán shàngwèi bèi jiēshì.

The source of these fossils has not yet been revealed.

他引用了多个学者的观点作为文章的来源。

Tā yǐn yòng le duōge xuézhě de guāndiǎn zuòwéi wénzhāng de láiyuán.

He cited the views of several scholars as sources for the article.