Extract email from website

How to extract the email of the corresponding author of a publication, like: https://doi.org/10.1039/C7CS00709D with Pentaho Data integration?

https://doi.org/10.1039/C7CS00709D as rendered HTML
https://doi.org/10.1039/C7CS00709D (excerpt of HTML source code)
  1. Get the HTML of the publications via REST Step, store it in one field.
  2. Extract email via “Regex evaluation” step using the Regex
    with the step options:
    • Enable dotall mode
    • Enable multiline mode

The first email appearing in the HTML will put into the filed email.

Alternatively the Online Service https://www.convertcsv.com/email-extractor.htm also provides a nice possibility to extract emails from several websites: