Is money earned from preparing research papers using e-books uploaded to the Internet—despite the mention of copyright—considered unlawful money?

The fatwa states that copyrights are owned by their holders, and it is not permissible to infringe upon them. Therefore, it is not permissible to benefit from photocopied books without the permission of the copyright holders. As for the money earned from research that benefited from published books without permission, it is permissible from this aspect because it is from the effort and work of the researcher.