Hi!
I’ve been asked if the use of Crossref logo is free, I mean… I know it is, but I didn’t find any information on the website (Brand & logos - Crossref) where this could be confirmed. The intention is to use the logo to promote a paid course regarding DOI, so I guess the organisers just want to avoid any future trouble 
Hi @BrunaErlandsson!
You can find logos here: assets.crossref.org.
Does that help? Who is organizing the event?
Rosa
Hey, thank you
It is an ABEC project. It is called ABEC Educação, the first course that is already released is about Peer Reviewing Process, and now they are working on extra modules/courses… (such as this one re-DOI)