Dr. Wellum has recently written a book titled: "The Person of Christ: An Introduction". This volume is part of the Short Studies in Systematic Theology. You can find a copy of it here:
https://www.amazon.com/Person-Christ-Introduction-Systematic-Theology/dp/1433569434/ref=sr_1_1?keywords=the+person+of+christ&qid=1644886339&sprefix=the+person+of+christ%2Caps%2C252&sr=8-1
