I found a 2016 presentation by an author in my niche field and want to get permission to reuse and modify a few of his figures for my master's thesis. But, the presentation doesn't has any copyright notice.
I can't find a way to contact him. I tried:
- Contact information on any support or paper he participated in; there is nothing.
- The website of his academia doesn't allow contact from un-authenticated users.
- I can't find him through the contact list in the email system of my academia.
- His LinkedIn account has a lock to not send messages to him.
He is still in academia, participates in juries of theses, and advises students. I am running out of options. Do I need to forget about using his figures?