I was recently asked to review Dean Furlong’s monograph The John also called Mark for the Catholic Biblical Quarterly and the review should be out next July. You can check out the author’s distinct thesis in the abstract of the book posted in the link, but without giving the details away I will just note that it is a thoroughly researched examination of the Patristic and Medieval traditions identifying John Mark with either the second or the fourth evangelist. He has also published The Identity of John the Evangelist: Revision and Reinterpretation in Early Christian Sources.
If you are interesting in how my views differ on the reception of the evangelists Mark and John, you can check out the following sources:
- The Beloved Apostle? The Transformation of the Apostle John into the Fourth Evangelist (Eugene, OR: Cascade Press, 2017). See also “Would the Real Elder John Please Stand Up?” Bible and Interpretation 2017.
- The Gospel on the Margins: The Reception of Mark in the Second Century. Minneapolis: Fortress Press, 2015. See also “Why Did the Gospel of Mark Survive?” Bible and Interpretation 2015.