Here is a second resource journal brought on because all the portraits I've been doing this week! The first journal was Stuff to Listen to While Drawing. This is basically a huge list of tutorials and references. At the end I talk about two 3D models of heads that have been super useful to me recently!
General: Face Tutorial by alexds1 Face Tutorial by phobs Reference Head and Face by what-i-do-is-secret Men that look like men by what-i-do-is-secret