If you are referring to published research, such as in a journal, contact information is usually included, such as the author's institution or affiliation. If an email isn't part of that information, you can search the Internet search the institution to obtain contact information.

If the research is in a book, you can contact the book's publisher for contact information. Or you can do an Internet search for the researcher's name, which will usually provide information on the researcher's affiliation, and contact them through that institution.

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