Hermeneia: The Johannine Epistles: A Commentary on the Johannine Epistles
by Rudolf K. Bultmann- You will need to have a Tweeter/FB account. Instruction:
A classic commentary on 1, 2, and 3 John from a well-known name in the field of biblical studies. Rudolf Bultmann addresses issues of authorship and source criticism into his discussion of the epistles, largely siding with Haenchen and Schnackenburg.